FOOD SOURCES OF CALCIUM
1. THE DETERLIINATION OF CALCIUM
IN MEAT COOKED 1ITE ACID
MAPLE COLE BEALS
A THESIS
su1iiitted to the
OREGON STATE AGRICULTURAL COLLEGE
in partial fulfill-nent of
the requiretnents for the
degree of
MASTER OF SCIENCE
JUNE 1935
S
APPROVED:
Redacted for privacy
ssor of Foods and Nutrition
In Charge of Major
Redacted for privacy
Assistarr Professor of Orgauic Chemistry
Redacted for privacy
Chairman of Sthoo1 Graduate Cormiittee
Redacted for privacy
Chairman of College Graduate Council.
DOTLD MW 2ODNEY BEALS,
.IHOSE COOPERTIOT HAS
THIS HEIS I
rJJJIS STUDY
AFFEOTIO1TA1ELY
flED ICATED
2OSSThL,
TS
ratefu1 appreciation is ecended to
rcfesor Jessrnine Chapman Willi'iis, Iead
of the deparl2nent of Foods snd iTutrition,
who directed this study; to Dr. Charles S.
Assistant Professor of Organic Chemistry,
who supervised the chemical analyses.; and
to all others who have given helpful advice
and criticism.
oase,
TABLE OF CONTENTS
INTRODUCTION
1
The Probleaa
1
The Application of Acid Cookery ------------------------
2
FOOD SOTJRCES CF CALCIIE --------------------------------------
7
Dietary11oance --------------------------------------
7
na1yses of Foods --------------------------------------
6
CALCIUM BALITOE STUDIES --------------------------------------
12
Vegetables ---------------------------------------------
12
Legnes------------------------------------------------
13
Cereals------------------------------------------------
14
Fiber--------------------------------------------------
16
FattyFoods --------------------------------------------
16
Oranges------------------------------------------------
20
Mi1I---------------------------------------------------
21
Intake and storage --------------------------------
21
Sources of Mi11 ------------------------------------
22
Forms of Milk -------------------------------------
22
Milk Products ------------------------------------------- 24
Ice Crean -----------------------------------------
24
Cheddar Cheese ------------------------------------
25
CALCIUM UMTABOLISM -------------------------------------------
26
Absorption ---------------------------------------------
26
Fat and Fiber -------------------------------------
26
p1-I of the Digestive Tract -- ----------------------
26
C ONTENTS
27
Acid-base Balance
Vitamin D
-
28
Ca:P Ratio
29
Balance of Other Minerals ---------------------
30
BLOOD CALCIUM --------------------------------------------
31
State of Blood Calcium -----------------------------
31
Parathyroid Hormone --------------------------------
31
Vitamin0 ------------------------------------------
32
Acid-base Balance -----------------------------------
33
Serum Protein and Phosohorus --------- --------------
33
C .A.LC IU!
EXCRE TI ON ----------------------------------------
BONE FORMATION -------------------------------------------
36
Chemical Composition --------------------------------
36
Method of Formation --------------------------------
37
Effect of Vitamin L) --------------------------------
40
Variation of Composition of Bone -------------------
40
Diet ------------------------------------------
40
Rate of Growth ---------------------------------
41
Age -------------------------------------------
41
Sex -------------------------------------------
42
Breed -----------------------------------------
42
Variability of Parts of the Same Bone ---------
42
CARTILAGE ------------------------------------------------
Formation and Ca1cum Content ----------------------
44
CONTENi
The Cartilage of the &ples
45
EX?ERL:NT& --------------------------------------------- -
47
T'e Problem ---------------------------------------A. Smnlin of Materials --------------------------B. Preparation of Samples for na1yzis -------------
47
C. Supplies and Reagents ---------------------------
50
Chinese Vinegar -------------------------------
50
auc ----------------------------------
50
erioan Vinega ------------------------------Potassin Perrnangsnate -----------------------Other Reagents -------------------------------0. Ca1ci Determinations --------------------------E. Spareribs --------------------------------------F. Beef Shortribs ----------------------------------
51
RESULTS JITII SPPRRIBS -----------------------------------
58
The Effect of Fat Extraction -----------------------
58
The Effect of Different Azaonnts of Vinegar ---------
60
The Effect of Different Acidities -----------------The Effect of the Liquid Ingredients ---------------
62
Soirbean
47
48
51
51
52
54
56
63
A Comparison of the Effect of Chinese and Iixrierieaii
Vinegar --------------------------------------------
65
The Effect of Boybean sauce with Chinese and Aerican.
Vinegars ------------------------------------------A Comparison of Meat, Bone, and Cartilage on the
67
C O1TETS
Calcin Yield
-
The Effect of the
e of the Pnial on the Calciixu
The Yield of Calcii from a Jine ionth's Animal
73
74
The Effect of the Liquid Inredientc on the .oat
and Bone vithout Cartilage -----------------------------
A
75
rn1ary of the Effect of the Liquid Ingredients
----------------------------------------
77
A Sary of the Results rith Soareribs ---------------
79
----------------------------
81
I0RT RIBB --------------------------------
85
SUJTARY-----------------------------------------------------
88
CONCLUSIOITS -------------------------------------------------
89
BI3LICG:AY ------------------------------------------------
90
onthe Calcit
DISCUSSIOi: 3? EESTJLTS
ThJUT
ITE BCE?
0RK
LIST OF TIBLES
Table I. The Effect of Fat Extraction -------------------
59
Table II. The Effect of Different
nounts of Vinegar ----
60
Table III. The Effect of Different Acidities ------------
62
Table IV. The Effect of the Liquid Ingredients ----------
64
Table V. The
foct of Chinese end 4rtericen Vinegar
in the Cocking Solution ---------------------------------
66
Table VI. The Effect of Soybean Sauce with Chinese
and.merican Vinegars -----------------------------------
68
Table VII. A Comparison of Meat, Bone, and Cartilage
on the Caloirni Yield ------------------------------------
70
Table VIII. The Effect of the Age of the Animal on
theCalciia ---------------------------------------------
73
Table IX. The Yield of Calciim from a Nine Month's
Animal ---------------------------------------------------
74
Table X. The Effect of the Liquid Ingredients on
the Meat and Bone without Cartilage ---------------------
76
Table XI. A Summary of the Effect of the Liquid
Ingredients---------------------------------------------
77
Table XII. The Calcitmi Yield from Beef Short Ribs -------
85
CCi) SOURCES OF CALCIJM
I
T-IE DE TERtIhIQN OF CLCIt
II 1EAT COOKED yii ACID
Ii RODUC ?ION
This investigation was suggested by a report on ttp8j18 Sources
of Calcii
and. Phosphorus in the Chinese Dietu by Pik-7Ian IIoh,
Jessm:Lne Chazan .[illierns, and Charles S. Pease recently published.
in the Journal of Jutrition.
serving of
(56) In the above study an individual
ork sDareribs cooked by a Chinese nethod was found to
yield 0.5504 gran of calciin, only 0.O75 gran of which was derived
from the cooking solution.
It seemed desirable to apply the some
principle of cooking with dilute acid to
erican dishes of meat
and, bone in an attempt to discover whether the yield of oalci
justir the procedure and result in a palatable dish.
rould
In order
to test the efficacy of acid cookery on the total calcirni in an
american dish, moat and bone were cooked with dilute
and the meat and solution were analyzed for calcii.
ierican vinegar
After spare-
ribs ccoked with .aerican vinegar gave results lower than Miss I-Ioh
(55) obtained in her Chinese dish of tsweet_scur_spareribsU,
series of experiments were conducted in an attempt to discover
whether the yield of calcin could be duo to any other factor
than the total acidity of the cooking solution.
Repetitions of the
Chinese recipe gave results ranging from 0.15 to 0.35 grom of calci
per serving, while one serving cooked with water alone :gave 0.46 gram
of calci, and another with dilute American vinegar yielded 0.55 gram
2
of calcium.
The astounding variations in calcium yields secured from
duplicating the recipe led to an attemp-U to discover the factors involved.
The effect of different cooking solutions and of different methods
of selecting samoles on the ealelum yield is the theme of this study.
The traditional use of acid by the Chinese in preparing meat and
bone dishes as a food for pregnant and nursing mothers in a country
where calcium rich foods are limited is no less interesting than the use
of the ash of 'salt wort' as a condiment by a certain African tribe in a
l;-froo
the "salt wort" being one of the few plants 1Q1o'm to
contain more sodium than potassium.
aration of meat or broth
Chinese.
(98) The use of acids in the prep-
rom bo:.o, however, is not confined to the
cCance, Sheldon, and Widdowson (91) state that at the present
time in England a broth ore-od
bones, mixed vegetables, and. dilute
vinegar appears to be widely used in the feeding o
infants.
These in-
vestigators have recently analyzed this liquid, prepared with the bones
of veal, and have cpared its nutritive vaiae with milk.
In European countries acids are quite generally used in the cooking process both to make tough cuts of moat more tender and to give
flavor to the meat dishes.
Perhaps the most widely 1own recipe is that
of "sauer brauten", German sour beef, a variation of which may be found
in almost any book containing meat recipes.
(76) Rump beef roast with
seasoning and bacon is covered with whole or diluted vinegar and soaked
from three days to one week.
and brovrn sugar.
gravy.
The meat is then rolled in flour or flour
If the neat is roasted, the vin:jar mar be used in the
The soaking solution may a10 be used in the cooking process.
Pioricans, however, use acid chiefly for flavor in preparing
and serving meat.
The use of tomatoes in cooking meats as well as
in sauces to be served with meat both in foreign and domestic
recipes is too cornon a practice to merit elaboration.
also is served with meat.
Lemon juice
Other dishes prepared with acids are:
pickled pig's feet, Pork spareribs with sauerkraut and diplings, pork
spareribs with baked apples, ham baked with pineapple, Swedish tongue
with vinegar, lamb stewed in tomato sauce, mutton baked with apples
and onions, and sour cream roast.
books include the use of:
Further suggestions noted in recipe
syrup loft from pickled fruits as a flavor-
1mg for meats, prunes cooked with meat, raisin sauce made with a base
of cider arid served with ham, and, sour cream as the liquid of veal or
lamb gravy.
During a course in Experimental Cookery, the writer had occasion
to use certain acids with short ribs of beef in an effort to produce
a palatable meat and bone dish with acid.
The basic recipe was
devised by Mary Bertram as part of her work on an unfinished thesis
now in progress under the dirction of the department of Nutrition at
the Oregon State Agricultural College.
The recipe included 225 grams
of meat and 50 grams of bone cooked in 430 cc. of liquid with 8 grams
of sugar and. 3 grams of salt for flavoring.
35 cc. of vinegar was con-
sidered the largest amount that could be included in the production of
a palatable Droduct.
The meat with bone was seared in an agate kettle.
Then the liquid aud seasoning were added and the covered mixture cooked
at 97 degrees Centigrade for three and one-half hours.
4
The acids compared vrere vinegar, lemon juice, citric acid, sour
milk, whey, rhubarb, gooseberries, tomato puree, and tomato puree with
vinegar.
Because of the varying acidities of these solutions, they
were used as part or all of the liquid of the above recipe in the following omounts:
Vinegar 35 cc., lemon juice 30 cc.
(
lemon), 2 per cent
citric acid 40 cc., sour milk 430 cc., rhubarb 250 cc., gooseberries 250
cc., tomatoes 430 cc., and 230 cc. of tomatoes with 20 cc. of vinear.
With rhubarb 24 grams of sugar was used, with gooseberries 16 grams,
while with tomatoes no sugar was used, and with the tomato-vinegar
combination the sugar was decreased to 5 grams.
The cooking media dif-
fering in character from. the vinegar were thickened with 5 to 20 grams
of starch mixed with 15 cc. of water and the resulting gravies
colored with kitchen bouquet.
Although the flavor was excellent the
curds of the sour milk product was displeasing in appearance.
The
gravy of' the meat prepared with whey looked appotiing but the flavor
was slightly bitter.
The rhubarb gravy was stringy but of fair flavor,
while the gooseberry gravy was curdy in appearance with an unattractive
lavender co1or and it had a peculiar twang not appetizing to most people.
The tomato gravy was acceptable both in flavor and appearance, although
the long cooking period did not imorove the tomato flavor.
ing acids were considered usable:
The follow-
vinegar, lemon juice, citric acid,
whey, tomato, and tomato with vinegar; while lemon, citric acid, tomato,
and tomato with vinegar were regarded as the most acceptable.
The whey and the tomato puree solutions approxated a total titratable
acidity corresponding to 0.15 N, the acidity of the cooking solution used
by Miss Hoh (56) in her work with spareribs.
Citric acid furnishes a
very inexpensive acid. if purchased in bulk and. made up to voluno at homo.
The cost of a 2 per cent solution thus prepared was approximately two
tenths of one cent for 50 cc.
To determine how high a degree of acid
would be palatable , meat with bone was prepared with citric acid at
three levels:
50, 90, and 130 cc. in 430 co.of solution.
The 90 cc.
concentration, which gave an acidity to the cooking solution corresponding to slightly less than 0.15 N, was the most acceptable.
Soaking the raw moat and bone in the most concentrated of these three
acid solutions for 24 hours materially decreased the cooking tine and
increased the tenderness of the meat.
The acid flavors the solution rather than the meat.
A palatable
stew can be produced by adding rice, vegetables, and thickening to the
meat and solution or by adding vegetables and thickening alone.
Since the acid hardens the cellulose of the vegetables, it was found
advisable to cook the carrots before adding them to the stew.
The production of a soup may offer another method of oonserving the
cooking solution.
If a new method of preparing meat and bone can be
found which will sufficiently increase the calciun of the edible portion,
it will undoubtly result in the creation of palatable dishes.
This
study is an attempt to determine the underlying reasons for the high
yield of calcium from the Chinese recipe in order to apply these
principles to the preparation of Anerican dishes, thus adding a now and
economical source of calcium to our dietary.
The utilization of calcium
from this source, in comparison with such foods as milk and carrots,
should be detertninod.
A survey of the limited foods that furnish
calcium in appreciable eounts oonvin.oes one of the desirability of
increasing the coirnnon sources of this important mineral.
7
FOOD $OUhC:
r4J I JL.,tS
r
jL,j
OF CAJCITJM
tflJ
Food is the natural source Oi Ium in the bO although a
Small araouit may be incidently ingested as an inorganic constituent
of some drinking waters.
To keep the body in calcium
the output must not exceed the intake.
uilibrium
Since the sezee food may vary
in calcium content, since calcium may be lost in preparing food for
hc table, and since absorption is not 100 per cent efficient, a 50
per cent margin of safety is allowed in estimating the
standard.
aloiin
hitherto, 0.68 grem of calcium a day has been considered
sufficient for an adult, but more recent practice favors 0.75 to 1.0
grsm as optna1.
(124) (79) Shean (125) (127) believes that the
rapid oalcification in the growing animal hastens maturity and lengthens the span bot:reen maturity and senescence, and that to secure this
storage, the factor of
rime importance is a liberal allowenco of cal-
cium in the diet, which he places at 1.0 gram a day for the child.
In the last tro months of human Pregnancy,
Toverud and Toverud (143)
found an intake of 1.7 grerns of calcium a day necessary to prevent
negative balances.
Shukers, -:acy, NLms, Donelson, and huncher (130),
in a study on three lactating women, found that 41 per cent, 37 per
cent, end 15 per cent, respectively, of the ingested calcium
was secreted in the milk.
A1JALYSES OF FOODS
lilt is difficult to nteet the optimal allowance of oaloij
out the incorporation of milk in the diet.
with-
Because of the adequaoy of
supply in this country, its palatability, its diversity of uses, and
its comparative richness in othor .food factors, a pint of milk a day
for adults and a quart for children is considered by some authorities
as a wise and economical practice.
in very small amounts,
While most foods Contain calcium
he total intake from a fow foods relatively
high in calcium together with a pint of milk usually meets the daily
optimum fo' adults.
Sherman (123) gives these figures as the approximate amounts
of calcium in 100 graiiis of edible substance;
Food
Grams
Cheese
0.931
0.239
0.160
A].monds
Beans,
dried
Egg yolk
Milk
0.137
0.120
0,089
Walnuts
Peanuts
Oatmeal
0.071
Eggs
0.067
Turnips
Carrots
Prunes, dried
Cabbage
Oranges
0.064
0.056
0.054
0.045
0.045
0.045
0.029
0.020
0.014
0.009
0.009
0.007
0.007
fl-ieat, entire grain
Beets
White flour
Potatoes
Bananas
Rico, polished
Apples
Beef
0.069
Many other studies have beer made to determine tho oa1ciiX
content of the various foods.
A serving of cauliflower or of spinach
is estimated to supoly one-tenth of the daily requirement, while a snailer amount is derived from other calcium rich vegetables such as carrots,
cabbage, celery, and turnips.
fruits rich in calcium.
Oranges, grapefruit, and figs are
Molasses is moderately rich, while meats and
grains are classed among the poorest sources of calcium.
(25)
The extremely low calcium content of meat was emphasized in a recent
analysis.
Calcium averaged 0.0144 gram per 100 grams of moist weight
in trimmed beef muscle and 0.0198 gram in untrimmed muscle.
(142)
In the thesis mentioned, a Chinese method of cookery was tasted for its
effect on increasing the calcium of the meat and solution.
(55)
The object of this present study is to investigate the possibility of
devising a practical way of producing palatab].
Jthiericen meat dishes
rich in calcium.
Variety of seed, type of soil, fertilizer, and irrigation affect
the calcium content of grains.
For these reasons, Holmes (59) found
it advisable to analyze each lot of corn used in rachitogenic diets.
Feeding experiments indicate the desirability of using a calcium rich
variety of wheat for hian and animal consumption.
(4) Bishop (10)
has conclusively demonstrated that a particular variety of plant
cannot be considered to have a constant calcium content.
There was a
marked tendency for the calcium and phosphorus to vary inversely ii the
Alabama vegetables raised on five tyPes of' soil, with some plants grown
in the green-house while others were grow. outside.
Cowell (29) found
that the calcium oontent of the outermost leaves of cabbage may be
10
twenty to thirty tines as great in smer as that of the inner leaves.
Different varieties of plants grown under the scme conditions may also
vary widely.
Thus, a diet adequate under one set of conditions might
prove deficient under others.
Cream cheese, neufchatel, cheddar, pro-
cessed, and. rennet and acid types of cottage cheese, prepared under
controlled conditions, were analyzed for calcium and phosphorus.
(90)
Cheddar cheese was found to contain approx_mately ten times as much
calcium as the soft cheeses, while the rennet and acid types of
cottage cheese were similar in calcium content.
mined tt, in herring, the P:
between 2
vcnber and January.
DeClercq () deter-
Ca ratio increased from 0.28 to 0.78
The available calcium was reduced in
milk when thc cows were confined to their stalls for 1on: periods.
(72) Thus, the calcium content of foods, or at least the available
calcium, is not a constant factor.
Analyses of foods from the tropics indicate the limited sources
of calcium in that re ion.
(ioi) In Europe, the use of liberal cmounts
of cheese in the diet constitutes the main source of calcium.
(25)
In China, calcium is derived from the extensive consumpion of eggs,
with their low but well utilized calcium, the general use of the soybeen, and, possibly, from bony cuts of moat.
mature and
(144) (55) Both the
rnriature soybeans are rich sources of this valuable mineral.
(i) (6) The Chinese infant gets the maximum protection from the mother's
milk by an extension of the nursing period until the child is three or
four years old.
That Europeans and Orientals are not too well protected
is shown by the prevalence of calcium deficiency diseases.
Even in
11
America, where milk, a rich source of calcium, is so extensively used,
Sherman (123) found in analyzing 200 adult dietaries that 16 per cent
of the oases were receiving less than the minnvm requirement of
0.45 gram of calcium per day while 52 per cent were receiving less
than the optimal standard of 0.68 gram.
(13) Sherman (123) believe8
that calcium, more than any other mineral, is liable to be deficient
in the American diet.
The calcium content of the intake is, however,
no measure of the degree of utilization by the body.
In order to
determine the comparative effectiveness of a food as a source of calcium
metabolic studies are made, preferably, on human beings.
12
cL.fIUTT dfj.:fc1
fTDIE
JIlT DIfFER II Ff0110
TEJg i::flIJO
I. nipnJjo
of etudies have been made on man to test the eff5.cionc'j
of djfferet vegetables as sources of calcium.
Iicflucage and Mondel
(90) concluded, as a result of a balance study on dogs
that green
vegetableo (carrots and spinach) mere not satisfactory substitutes for
for milk.
Later, however, exceriwenis on human beings have given favoroor utilization with
able results, which leads one to aus,ect that the
dogs may have been due to some factor other than the food source of the
calcium.
found that when 05 cor cent of the calcium of the
Rose (119
diet was derived from carrots one adult had
ractica11y the some
retention as on a diet in which 70 uer cent of the calcium was derived
from mill:, while three of the four fercons tested were in positive calcium balance.
Thus, it was found cossible to meet the calcium reauirc-
mont aiUh carrots.
Blaiheraick and Long (ii) concluded from the use
of different vogetablec (canned asparagus, cooked celery, cooked spinach, boiled cabbage, and steamed surneer eguash) that vegetables were
capable of mootin
ly, although not
the calcium and ihosclrorus needs of ran as .offcctive-
uite so 3fficientiv, as milk.
McLaughlin (.) oh-
tamed a nositive balance in six women, arhile the seventh heat in
calcium equilibrium on a diet in which 70 aer cent of the calcium was
derived from spinach.
Storage on the control diet, in which 79 per
cent of the calcium was derived from milk, was not increased enough to
consider one sourco superior to the other.
This seemed surprising be-
cause of the high oxalic acid content of the spinach.
The utilization
13
secured by
;io adults on a diet in which 93 per cent of the oalci
was
derived from leaf lettuce oroved superior to that of the control period
in which 88 oer cent of the diet was derived from milk.
(84) The results
of the studies seem to justify the conclusion that for the adult vegetables are as satisfactory a source of calcii
as milk.
with children have not had, such favorable results.
The studies
In the much
quoted expersaent ol' Sherman and ilawley (126) vegetables did. not prove
so effective a source of oa1ciii as milk for the growing child.
Spinach and carrots were the vegetables in one of the series, while in
another celery and string beans were also used.
In five series of
expernen'bs with infants ealoji retention was decreased when spinach
or carrots were added to the diot.
34)
is
Soy'oean.
since in China milk is impractical as a food, except
for invalids and babies, calciwa is supplied chiefly by vegetables,
particularly the soybean in the foa of a curd.
(i)
levels of
protein were used in the diet to comare this source of calciwa with
milk.
The higher protein intake of sixty-five to ninety grams a day
Per person was found much more favorable for calcjt
retention.
Res-
ults indicated that, in the presence of adequate protein in the diet,
the soybean curd was as efficient as cow's milk as a source of calci
in the Chinese diet.
Soybean is used by the Chinese in other ways, not
the least intoresting of which is the production of soya bean milks.
(lii) (27) (137) Such foods are Proving successful for oriental infants
as well as for others to whom cow's milk is not acceptable, as in cases
14
of food allergy.
(74)
Navy Bean.. Since the calcium from the soybean is so well
utilized, it would seem that our navy bean might also prove an
excellent source of calcium.
When baked and pureed beans were fed
at two protein levels, however, calcium assimilation did, not improve
with increased nitrogan rotontion, although the negative balances were
slightly more favorable wi
the pureed beans.
(108) The fact t-ht focal
calcium was high throughout, decroasing slightly during the series with
pureed beans, when the fiber was broken up, suggests that the poor
absorption of calcium may have been due to its association with
indigestible matter.
Two other possible explanations for the poor
absorption are the decreasing effect of carbohydrates on the gastric
juice and the basicity of the diet, neither of which appear to be the
probable factors.
Possibly on a higher calcium intake equilibrium
might have been secured, but an intake level of 5.5
-..
'd11igrams
of calcium per kilogram of body weight, an amount sufficient from
certain other vegetables, was too low when 80 to 85 per cent of the
mineral was obtained from beans.
Furthermore, the calcium from beans
might have been better utilized if fed in smaller amounts than the.
four ounces per person per day.
CEREALS
To determine the ttanti_caloifying
effect of cereals when used
in large enounts, refined wheat and oabrieal products were used in the
diet,
(22) Two girls, aged twelve and thirteen years, both stored
calcium on the wheat diet while on the oatmeal diet one was in
15
negative balance.
The four boy&, who were of nursery school age, stored
unusually large amounts of calcia.
This excellent storage may have
been partly due to their larger mineral intake,the more favorable
Ca;? ratio in their diet, the fact that they were receiving irradiation
at school, or a combination of all of these factors.
on oats, however, was less than on wheat.
Their retention
The two. adults, although in
negative balance during both periods, retained more calohmi when wheat
was used.
In all cases the retention on oats was loss than on wheat,
while the fecal loss was greater onthe oats.
It is relatively easy to produce experimental rickets in
laboratory animals by including large amounts of cc real in the diet.
Forbes (38) attributes rickets in children and domestic animals largely
to the too generous incorporation of cereals in the diet and the
exclusion of other foods richer in minerals.
Mollanby (95), the firm
believer in an anticalcifying property of cereals and its alleviation
by vitamin D, again advises diminishing the cereals for children and
for pregnancy and lactation to insu"
ly of the teeth.
better calcification, particular-
Porter and Levin (109) (110) fed proshcool children
plain and irradiated cereal, but storage was so varied that no
conclusions could be drawn regarding the retention of ca1oiii.
Bruce
and Callow (20) attribute this anticaloifying property of cereals to
the unavailability of 50 to 80 per cent of the phosphorus in the form
inositol phoshoric or phytic acid.
This substance is not easily
hydroylzed to an assimilable form without acid.
with one
&j treating the cereal
er cent HCL they have been able to bring about increased
calcification in rachitic rats on a high calciim diet in which the
phosphorus was largely derived froni cereal.
Forbes and Irving (39)
have reported that the ca1chn of the uaturally occurring salt,
ca1cit-magnesium-inosite-hexaphosphorio acid, was as well absorbed
by rats as calcium chloride.
Ste,nboc
In view' of the fact that Templin and
(141) have found the tibia of the growing rat more Sensitive
to mineral deficiencies thi the teeth, it is of interest to note
two recent contributions in oonnection with the effect of cereals on
the teeth.
(73)
In a study over an extended period Kooh.no and Bunting
found that caries was unusually low in an orphanage on a type diet
in which 40 to 50 per cent of the diet, in Calories, was derived from
cereals.
The low incidence of caries could not be explained by the
intake of calcium, phosphorus, or vitamin D.
(80) Lilly and iiley (77)
fed rats coarse cornmeal in an otherwise satisfactory diet.
In 125
days all of the rats had developed caries, while no caries resulted
when the cornmeal was made soft by cooking or was ground sufficiently
fine.
In this case, the form rather than the souroe of the cereal
appeared to be the main factor in the production of the caries.
Thus
more may renjain to be learned regarding the effect of cereals on
palcification and the optiniimi aiount to be included in the diet.
The
effect of the cellulose constituent of cereals will be further diused under fiber.
FIBER
Practically all food sources of calcium except milk are characterized by the presence of fiber.
legumes,and cereals.
It is particularly abundant in vegetables,
Bloom (12) concluded from feeding rats spinach
17
that roughage,in itself, had no harmful effect on calcium assimilation.
rats.
Asham (2) concluded that bulk does increase the focal calciin in
Hushes and Caves (63) foundthat the exclusion of roughage, formerly
considered necessary, from the diet of calves for eight months was
To what extent fiber affects
accompanied by good storage of calcium.
calcium assiii1ation in humans is always a question and one that cam
best be answered by balance experiments.
It w.s previously noted that carrots and spinach retarded the
calcium retention in infants.
(34) Schultz (120) fed infants cellu-
flour, dried spinach, pureed spinach, raw spinach, or a mixture of
mineral salts similar to those found in spinach,
lie cone luded. that
roughage, as such, has little, if any, effect on the retention of
calcium, that the amount of calcium retention is related to the amount
matter
of feces eliminated, and that mineral retention from vegetable
is negligible in infants.
calcium for growin
when vegetables were used as a source of
children Sherman and Hawley (126) found them infer--
br. to milk.
Adolh (1) suggests in his metabolic study with the soybean that,
while the diet was not characterized by an excess of fiber,the effect
of roughage on calcium assimilation in the Chinese dietary remains unanswered,
The poor retention of calcium in the navy bean study together
the
with a slightly improved assimilation when the beans were fed in
fori of a puree, in which the fiber was broken up, suggests the possibility of interference from fiLter.
Is it likely that the poorer as-
similation of calcium from oatm,al may be due to the presence of more
indigestible roughage than in the wheat?
Mango]4 (86) refers to
18
re completely
Rubner's conclusion that the savoy cabbage and carrots
digested and, to a large extont, the potato and spinach.
He further
gives the theory of Rubner and Lindros, who believed that the aleurone
cells of the cereal grains pass through the intestines without
dissolution of their walls.
Ho also includes these percentages from
Lohriseh for the fiber digestibility in the following fools:
white
cabbage, 100; carrots, 95; spinach, 90; bre, 59 to 8F; and split peas,
45.
Langold states that feces on a diet rich in cellulose increased
by more than the amount of roughage, because of the increased intestinal secretion.
The flora of fermenting bacteria in the intestines can
break dom raw or cooked cellulose, the younger parts more easily than
the older structures.
Thus it seems that the condition and source of
the fiber, the food combination in the digestive tract, and the
intestinal flora may interfere with calcium assimilation.
FATTY FOODS
When 73 per cent of the calcium of the diet was derived from
alnonds calcium equilibrium was secured in twelve adults on 5.6 to
7 milligrams of calcium per kilogram of body weight.
This utilization
was about as economical as when 'O to 74 per cent of the calcium was
supplied by milk.
(117) However when almonds contributod 85 to 86
per cent of the calcium of the diet the intake had to be increased to
from 8 to 12 milligrams per kilogram of body weight to maintain
calcium equilibrium.
It seems surprising that it is possible to consume
such a high fat di.et without digestive disturbances.
Nevertheless the
the digestibility of almonds showed that utilization was almost as high
as for oatmeal mush in a simple mixed diet.
Thus, in sp.to of the high
19
fat content of the diet, the loss of calciii was only three to four
per cent less than in an average mixed diet.
Ca1ci
was also well
assimilated in cheddar cheese, another food. rich in fat.
Either high or low fat in the diet has been thought to react
unfavorably on calcij
assimilation.
Holt and Fales (60) found.
more calcium oxide in the stools of ohildren on a diet markedly reduced. in fat than in the stools of normally fed children.
Hic1nan (50)
observed that underweight children absorbed more calcium in the presence
of' a generous supply of fat in the diet.
Gaossler and MeCandlish
(41) concluded that the focal loss of calcium as insoluble soaps in a
high fat diet was not important in dairy cowS.
In a hiznan study
Mallen et al (85) was likewise unable to discover any difference in calcium assimilation in a high or low fat diet.
Marek et al (87) reported
that the elimination of calcium as soaps was important only in a high fat
diet.
Nelson (103) found the loss of fecal calcium lower then average in
a ketogenic diet for epileptic children.
Boyd, Crum, and Lnnan (17)
found that increasing the fat of the diet for rats developed a favorable
acidity in the digestive tract and resulted in good. utilization of the
ca1cii
tion.
soaps of paLmitie and. oleto acid formed in the process of digess-Uerlund (148) obsex-ved, in fu1l-grovii rats, the triolein was
quite vrell absorbed while trioalraitin raised the fecal calcium.
Thus
fat, per Se, in moderate amounts in the diet does not appear to affect
calcium absorption, although the higher molecular fats, including olein,
are more unfavorable to calcium absorption than the by: noleou1ar fats.
20
JUICE
ORA
Then
00 to 700 cc. of orange juice was added to the diet of
two children ca1ci-c retention was increased by more than the
amount of calcii.rji in the oranges.
(26) Furthermore the gain in )veight
was such that it could not be explained by the additional Calories
from the oranges.
Better growth in children when oranges were part
of the diet had previously been attributed to their supply of vitairi
B or C.
The explanation for this great increase in calcium retention
is not clear.
It may possibly be due to one or. more of these factors
altering the diet from acid to basic by the addition of the oranges;
adding zno:e vitcmin &, B, or C to the diet; increasing the ealoin and
phosphorus intake , Which might favor furthor retention of these
minerals; increasing the gastrio secretion; or lowering the intestinal
ph.
21
TIILK
Intake and Storage.
hon herman and i-iawlev (126) observed
that storage of calcium in tho growing ohild was raised. 70 per cent
by increasing the intake of milk fr
750 to 1000 grams, a quart of
milk a day for each child became the dietary concept of optimal
nutrition.
In addition, this same study demonstrabed convincingly the
suporiorif
af u1k over vegetables as a source of calcizn for
children.
They further found that the retention of calcium was
increased somewhat with the age of the child.
eight children of three to five years,
In a later study on
anie1s et al (31) found no
significant correlation between the amount of calcium retained and the
amount of mill:: fed above a lint.
The greater storage, proportionally,
on a pint of milk a day may have been due to the fact that during the
earlier
art of the experiment the children were more poorly nourished
than later when more milk was given.
Uthough calcium absorption and
retention vary widely, Stearns and foore (136), Ogilvic and Peden (104),
and Jang ot al (147) have noted. a slight tendency toward an increased
daily retention of calcium per kilogram of body weight in undernourished children.
Ilunohor et ci (64) observed greater storage in growing
children when the intake was increased from 1.0 to 1.9 grams of calcium per day.
Stearns (135) gives 40 milligrams per kilogram per
day as a desirable level of calcium retention for artificially fed
infants and at least 10 milligrams rer kilogram for older children.
She found that retention per kilogram decreased rapidly in early infancy.
fter this, while the retention of calcium per kilogram decreased
22
slowly, the total amount retained increased with the greater iutake of
the older child.
The curve of daily retention per kilogram was found
to parallel closely the yearly increment in height.
(134). (136)
A pint of milk a day is the generally acc3pted allowance
for adults.
This amount is considered desirable, since it insures
the body of Shermcxi's daily miniaiumi requirement while it seems safe
to assie that the Other foods in the diet will supply enough
additional calcium to cover the margin of safety.
An increased
amount is recommended in pregnancy and lactation.
Sources of iJilk.
1n infant feeding Wang, Witt, and Feloher (l7)
found that the final retention of calcium from cow's milk was higher
then from hinan milk.
Although the fecal loss of this mineral from
cow's milk was greater, the higer calcium content of Cow's milk more
than comoensated for the increased percentage of calcium retained from
human riilk.
Swanson (138) found, in comparing a breast fed infant with
one on cow's milk, that the calcium retention per kilogram of gain in
weight was greater in the latter.
Forms of Milk.
Bell (6) noted a measurable loss in the soluble
calcium and phosphorus in milk heated to 170 degrees Fahrenheit or above.
This loss is apparently due to the heat and is proportional to the rise
in temperature.
Magee and Harvey (81) found that pigs retained more
calcium and phosphorus on raw milk, fresh or sour, than on heated milk.
This result was attributed to a loss of soluble calcium in milk from
heating.
In a study conducted by Kramer, Latzke, and Shaw (72) fresh
milk proved superior to pasteurized as a source of calcium for the
23
adult.
Ellis and Jitche1l (5
of the oaloii
believe that the lower availability
in pasteurized ailk for the growing rat is duo to the
destruction of soo unknown constituent of the cilk that favors its
utiljatjon.
ar.iols and 3tearns (32) found that jnfantr.
ust holding
weight gained when quickly boiled :iilk was used in place of pasteurized.
Furthermore, the fecal calciLn was less on the guickly boiled milk diet.
on:iz and Graham clOt) observed that the aborution of nitrogen, calcimi, phosphorus, and fat was not dininished when uickly boiled milk
was substituted gor raw milk in the diet of infants.
Ogilvie and. Peden
(io) staae that the dicestibility of raw and boiled milk is sLti1ar
in infants when the pH, the pen bic action, the free and total acidity,
the total chlorides, the soluble calci, and the non-protein nitrogen
of the gastric contents are used as indoxc
of the course of digestion.
The study of Kramer et a]. (72) showed as good retention of calcirni 2r
evaporated as from ::resh milk for adults.
In working with rachitic rats,
Honeywell, futohor, and Dahie (61) found a decrease in the ossifring
potency of evacorated milk in ceparison with the raw product.
was atiribuGed either to mineral loss or vitemin D destruction.
5Jüs
The
work of Kramer et al (72) signified that adu1t, as well as children,
retained more calcium fri fresh than from dried milk.
The effect of
vitamin Das a factor in absorption was illustrated by the superiority
of the calciim from the milk of cows allowed in the open in comparison
with milk of cows kept in the barn continuously for a long period of
time before and during lactation.
24
These investigators also concluded that the milk of the stall confined
cows was equivalent to dried milk as a source of calcium.
In a balance
study conducted by Willard and Blunt (149) three out of four children
showed improved calcium, phosphorus, and nitroge i retention when
evaporated milk was substituted for pasteurized.
With adults, however,
either Corn,, proved equally effective.
MILK PRODUCTS
Ice Cream.
Kramer, Potter, and Gilli.on (73) determined the calcium
balances of ten college women on a potentially acid diet such as might
be commonly used.
A diet in which ice cream furnished 1.06 of the
L.32
rams of total calcium was cornared with one in which 0.984 of the 1.25
grams of the total calcium was derived from raw whole milk.
The milk
in the ice cream was sweetened condensed sldnmied and fresh skjjmwd milk
both of which were pasteurized along with the other ingrecüents for
thirty minutes and then homogenized at 2500 Qounds.
ageing, the mixture was frozen.
After cooling and
The five of the ten persons on this
balance who were treated with ultra-violet irradiation showed no better
assimilation than the controls, while three of those receiving irradiation together with four of the controls showed more favorable calcium
balances from ice cream than from the diet with milk.
Thus it was con-
cluded that for adults condensed and pasteurized milk in ice cream was
as efficient a source of calcium as raw milk.
One might question the
significance of the results obtained from a balance in which the intake,
in both periods, was so fr above the estimated calcium requirement.
It would seem that storage of the mineral might interfere with the
25
interpretati.on of results.
Cheddar Cheese.
nerioan cheddar cheese, a food rich in calciti.,
was compared with pasteurized whole d1k to determine its relatiTe
value as a source of calcium.
Cheddar cheese ranks high among -the
cheeses in calcium content, the sample in this study containing 0.74
per cent calcium.
The intake in the period in which cheese was
a part ci' the diet was 10.2 milligrams of calcium per kilogram of body
weight, while the intake iii the control diet was 9.4 milligrams of
dalcium P'r kilogram of body weight. With such intakes Mallon, Johnson,
and Darby
83) concluded that the calcium from American cheddar cheese
was as well utilized as the calcium from pasteurized whole milk.
Chaney arid Alhborn (25) state that cheese is consuried in small quan
tities by Americans while in Europe it forms a very substantial
part of the diet.
-
This study suggests en easy method of increasing the
calcium intake in the American diet for those who do not like milk.
26
CALC IUM METABOLI SM
ABSORPTIO1
It camiot be assumed that the amount of calcium theoretically
computed for a given amount of ingested food will be actually absorbed.
The calcium content of a given variety of plant or animal product is
not constant.
consumption.
Calcium may be lost from a food in its preparation for
The extent to which calcium is available from different
food sources may vary, for examp].e infants and older children absorb
calcium from milk more completely than from vegetables.
The fiber or
fat content of the diet may possibly affect calcium absorption.
Other factors in the food combination may affect calcium absorption.
The individual may vary in his capacity to absorb calcium at
different times.
FAT PiD FIBER
The effect of these factors on calcium absorption was previously'
discussed at length under food sources.
TROF THE DIGESTIVE TRACT
Since calcium compounds are dissolved by roid, their absorption
can be increased by any factor that lowers the pH in the region of
the digestive tract where absorption takes place.
There is a question
as to what factor is the most influential in lowering this pH:
(a)
an increased seretion of HCL, (b) a decreased. secretion of the alkaline
intestinal juices, or (a) the production of acid in the intostines by
certain ingested foods.
(93) (115) (s) (23) (69.
27
The deressing effect of some foods on oaliu absorption has been
attributed to their stimulating effect on the alkaline intestinal
juices.
(23) The
boequent rise in pI resu1t
in the precipitation
of calcitmi phosohate in the region of absorption and thus decreases, the
available calcium.
Bergoim
attributes the increased absorption on
a diet rich in lactose to the production of lactic acid an4 its
reductioxi of the intestinal pH.
However, Robinson and Duncsm (113),
in working with rats, found that the influence of lactose depends on
the nature of the basal ration which, in a meat diet, did not appreciably lower the ijH of the digestive tract.
In a recent study of ab-
sorption in the rat, Cruto (30) observed that some cicii was absorbed in the stomach, the amount depending on the solubility of the
calcii salt and decreasing with the age of the rat.
The main absorp-
tion was found to take place in the cecum, while in the duodenti ca1oi'
elimination predominated over absorption.
Cruto (30) further found that
calcium was assimilated best when it was fed with. magnesium and
phosphorus.
AC ID-BASE BALCE
A diet slightly basic or neutral in respect to the acid and base
forming elements of intermediary metabolism is considered most favorable
for calcium metabolism. A base forming diet, which may or may not
increase fecal calcium, is aecomoanied by a decrease of urinary calcium.
(23) (15) It was previously noted that foods raising the pH in the in-
testines decrease calcium, absorption, while those loering this pH are
more favorable for calcium absorption.
Organic acids lower the pH of
th
intestinos but, since they are usually completely oxidized by the
body unless taken in ocess, thoy do not lower the alkaline reserve.
Oonverely, inorganic acids are not oxidizod by the body but are
eliminated as salts.
In a study on milking cows Fart, Steenbook,
and Hahrey (49) found that the addition of inorganic acid, to the diot
was folloned by increased absorption, which was, however, more thar
offset by the loss of urinary calcium.
Goss and Schmidt (44) were un
able to find any difference in the calcium and shosphorus storago of
young rats nursed by nothers that had been fed for some tine on
alkaline or on acid, diets.
coons et ci (28) secured the best retention
of calcium in :cuman pregnancy with a basic diet.
Shohi et ci (129)
found that rickets developed only on the acid diet when rats were
fed a standard diet which was altered to become acid, basic, or
neutral by the addition of HGL, CaCO'z, or NaOH.
his favors the
asrptiom that neutral or basic diets increase ca1cha assimilation.
Lorgan ot al (iDo), in an extenivo investigation with dogs, also
securod the greatost storage of calcium on a neutral or bn.se formlrg die-o.
Thus, a dIet potentially basic in the tissues but cola
in the digestive tract seems most favorable for calcitmi retention.
VIf,TIN D
One theory about vitamin D is that it increases the absorption
of calciun and phosphorus in the digestive tract.
(23) Sjoilema (132),
in his work with rabbits, noted that vitamin D was able to change
negs. lye balances to positive and under certain circumstances to
further increase retention when the calcium balance Was previously positive.
iT4llgoard (99), as a result of feeding experiments with pigs,
29
concluded, that it was clangorous to add. concentrates of vitamin D or
A and D to the human dietary without due regard to the mineral content
of the diet.
Although the effect may be negligible or favorable with
a satisfactory calcium:
phosphorus ratio, he is convinced that with
an excess of neutral calcium salts hyperoalcenia may be produced o.r
with insifficient calcium osteoporosis and tetany may de1op.
CALCIUM:
PHOSPHORUS RATIO
A sufficient
ouyi of calcium in the diet is the first essential
I
for good calcium absorption.
However, above a certain point, Rost,
Herbst, and weitzel (118) found that no benefit was derived from.
including additional calcium in the diet of a thirteen year old boy.
Rheimers (112) concluded that the retention of sufficient calcium by
young pi;s was dependent on the presence of adequate phosphorus in
the diet.
Spidelo (133) observed that, in young pigs, the ratio of
calcium to phosphorus was the most important factor governing the
metabolism of these minerals unless the calcium foil too law.
Bethke, Hick, and 'i(ildor (9) found that the ratio had a greater effot
on the growth and calcification in rats than the concentration or
level of these elements in the ration.
The Ca:
P ratio of 2.:
seemed the most favorable, especially with low vitamin D.
1
Sheman
(123), however, is of the opinion that, since the most desirable ratio
is constantly changing with growth, with optimal retention the ratios
will take care of themselves.
The addition of eithor element in excess
is thought to hinder assimilation by the fcrn.ation of the insoluble
tertiary salt of calcium phosphate in the intestinal tract.
(106)
30
BALUCE OF OfHER MINERALS
Cantarow (23) believes that the influence of inorganic elements
on absorption is of much less importance than calcium and phosphorus
in a favorable proportion.
He further states that an excess of magne-
ium, according to &vryer, Eai.mian, and stevenson, decreased calcium ab-
sorption as did am excess of potassium, according to Zucker and Llatzner.
Carswell and. Winter
24) found that a high and prolonged intake of
magnesium lactate with adequate phosphorus favored calcium storage in
two men and decreased calcium elimination particularly in the feces.
Bassett et al (3) observed that an excess of potassium had no effect
on the calcium, magnesium, or phosphorus metabolism in the diet of two
normal men and. one oedeniatous nephritio.
Haag (45) concluded from
a study on rats that a more or less balanced condition of calcium,
ag-
nesiuni, and phosphorus in the diet was essential to normal growth and
functioning.
Cantarow (23) states that in some uithicn way chlorine
seems to aid calcium absorption.
Husband (65) found that the addition
of sodium chloride or sodium citrate
cium and phos.horus retention.
o the diet of pigs increased cal-
3].
BLOOD CALCIUM
STATE OF BLOOD CALCIUM
The Annual Review of Biochemistry (72) gives the calcium content
of the blood in adults as 10.4-
fanz, 11.2 milligras
0.5 milligrams per 100 cc.; in in-
and in late pregnancy, 9.5 milligrams.
The
non.-iiffus1ble fraction comprises from forty to sixty per cent, while
the remainder is diffusible.
The non-diffusible calcium is thought to
consist largely of a protein bound compound with a fraction represented by a colloidal calcium-phosphorus complex adsorbable by barium
sulphate.
The diffusible calcium may exist as an inorganic bicarbonate,
a phosphate, and possibly a citrate-like compound controlled by the parathyroids.
A portion of the diffusible calcium is in the ionic form.
Benjamin (7) suggests that tro-thirds of the diffusible calcium is in
the form of a calcium-phosphorus complex adsorbable by barium sulphate.
Cajtarow (23) states that the equilibrium between the .iffusible and
non-diffusible fraction may be upset, while the total blood calcium remains constant..
hus, in low- phosphorus rickets of infants end rats
the calcium-phosphorus filtrable complex is decreased, while the ionic
calcium is correspondingly increased.
Although the method of control
of the various fractions of the calcium of serum is
somewhat of a
mystery, certain factors seem to act as regulators.
PARATHYR OlD ItOMO1E
The dissolution of an excess of tertiary calcium phosphate in the
blood or the formation of such a substance has been ascribed to
32
this hormone.
(23) Cantarow (23) states that some believe that the her-
none affects calcium metabolism primarily, while others are of the
opinion that the calcium is affected secondarily as a result of the
altered phosphorus metabolism.
Parathyroid secretion is biown to
cause an increased elimination of phosphorus, which results in a fall
in the phosphate ions of the blood.
In order to restore the phosphorus
equilibrium, calcium phosphate is mobilized from the bones.
This results
in a rise in blood calcium , which affects the non-diffusible fraction
slightly more than the diffusible.
Ham (46) enumerates these theories
of calcium regulation by the parathyroids:
ciixa-parathyroid
(a) the formation o
a cal-
ompound, (b) the formation of some unbjovn compound
with calcium, or (c) the resorption of calcium from bone and the subsequent liberation of calcium in the blood serum.
The source of the
liberated phosphate is usually ascribed to the trabeculae, although
Cantarow (23) states that Jaffe, Bodanaky,. and Blair believe that re-
sorption occurs primarily in the regions of most rapid bone growth:
the spongy bone of the metaphyses, the costochondral ji.ictions, the
cortioes of the shafts of bones, and the bones of the skull and lower
jaw.
VITJIN D
Vitamin 1) raises serum calcium and is accompanied by a rise in
serum phosphorus.
Jith sufficient calcium in. the diet this increase
of calcium in. the serum is explained by better absorption of the
element.
If, however, the diet is deficient in calcium vitanin D appar-
ently raises the calcium of the serum by withdrawing the calcium from
.7
the bones. (e seasonal variation of serio
oaloi
in infants is at
tributed to the decreased. eiount of vitamin D received from the si..mts
rays during the winter :..onths.)
Cantarow also refers to Clark's belief
that vitnin D increases the diffusible calcia by freeing calciisi ions
from the protein bound non-diffusible fraction.
Thus, the adrilnistration of vituain P raises both the oalciii and
phosghorus of th. blood, while parathyroid hormone raises only the
calcii fraction.
Furthermore, since the ad2ninistration of vita±n P
raises the caloi
and
hosohorus of
arathyroidectomied anr.wls, it
would seeni that vitamin f and the parathyroid hormone must function
separately.
However, the exact method of action of either remains
larnalv a. matter :f conjecture.
ACIP-B,SE
LJCH
The acid-baso euilibriirni of the blood is a factor in the regul-
ation of the ionization of serm1 cale. Therefore, the calciia ions
vary directly with the hydrogen ion concentration of the blood.
Fur-
thermore, the solubility of calcii is increased with the greater
acidity found. in. regions with a high carbon dioxide tensicn.
SPJJM PIOTIiT
p
(23)
3PpTJs
The non-diffusible fraction of the blood calci'i'. is largely
rotein bound.
Therefore, any variation, in the concentration of serin
protel:. affects the amount of serimi calohii in the blood.
The adnilnis-
tration of ahosphatec by way of the digestive tract, as well as intravenously, or undue retention of phosphates by the kidneys raises the
phosphorus of the blood and results in a cemaenzatory fall lxi. serii
34
calcium..
Thi1e carbohydrate ingestion lowers blood phosphorus, it
may or may not raise ser
calcin.
Caxitarow (23) refers to Pa1ner
and Eckles, who were able to produce hypophosphatemia accompanied by
hypercaloemia in cows on a diet low in phosphorus.
35
CALCIUM EXCRMION
Calcium is excreted to some extent by the kidneys
the epithelial cells of the large intsstine.
ut largely by
The study of the ex-
cretion of metabolio calciin by the intestines is complicated by the
presence of unabsorbod calcium in the feces.
ny factor that
decreased calcium absorption increases fecal calcium.
Marek, Weilman,
and Urbanelc (87) state that calcium is eliminated fr
the intestines
as calcium. carbonate, ciciuiri soaps, primary and secondary phosphate
salts, and also as salts of the organic acids.
Cantarow (23) notes
that the age of the person, as well as the weight and surface area, may
slightly affect calcium elimination.
Thyroid extract increases urinary calcium, slightly more than the
fecal, both being a result of the stimulating catabolic effect of the
hormone on body tissue, in this case the bony tissue.
An increase of
the parathyroid secretion raises only the urinary fraction and usually
follows a rise in serum calcium.
increased urinary calcium.
Vitenin D in excess also results in
Thenover the mineral balance is upset by the
absorption of an excess of sodium, potassium, or magnesium in the serum
an increase of urinary
r,icium follows, while an increase of serum
phosphorus may also result in a coinponsatory loss of urinary calcium.
Alteration of the acid-base balance of the diet or of the blood on the
acid side increases urinary calcium.
This increase in calcium eiore-
tion is inLpendent of the reaution of the urine and attributed , in
part at lease, to decalcification.
36
30flE :o:.L21ON
oici
TP0SITiC1
.Jthouh bone dates from antiauitv and has been used by nan and
SuLTbec to his scrutiny since prehistoric days, yet science is not
are,as to
'trha-b it is chemically or ho'r it is formed.
3eneral belief, a000rdin3 to Cantaro
The
(23), is that bone contains 85
to 90 uer cent of tertiary phosuhate and 9 to 13 per cent of secondary orLor'Ue. Shear and Kramer (p3) suggest the
rather than
Ca3(P0t):
in ossification.
1he
iportnce u CaP0
believe that, since bone
cannot be recrystallized., i is not a definite comoound. (12.2) L:keiise,
Irvind and Chute
(c
fixed procortions, th.
ztate that the minerals of bone do not exizt in
itto ore labile component. In contrast,
Taylor et al (133), vho base their conclusions on miscroscopie and X-ray
investigations, contribute the fomnula of 3Ca3(PO4)3.C2,ith X equal
to 002, F4, (oFi)2, 0, S0, Ca, or Mg. The typical siirr.rals present were
podolite, dahilite, and fluorapatite; while 9aHPO4.2H2Q was not observ-
ed to any exten. Bogert and Hastings (14) believe that the chief inorganic constituent of bone is probably a crystalline salt,
Ca003 NCaS(PO4)2, viith N aporoxireatin
bone.
qassran (23) concludes th:
the value of
in untreated
boac is a definite closed ring com-
pound because of the consfucy ci proportions of the salts of calcizi
phosphate and secondary carbonate. Furthermore, he suggests that, since
glycine derivatives from th.e hydrolysis of phosphoric acid, compounds
are stable, this favors thb azstrution that the organic matter of bone
and teeth are in chemical combination with phosphato-calci
carbonate.
37
(42)
nd so the controversy continues.
METHOD OF FCR1L'.TION
Freudenborg and Gyory (23) advance the theory that ca1oha is
deosited in coithina-tion with tissue proteins.
This compound 1a:er
unites with phosphate and carbonate -to form a phocoha-Uc-carbona-te-cal-
cin-protein complex, which subsequently liberates the orotein.
Rowland (23) states that caloiwa and phosphate ions are held in solution
by the serun in higher concentration -than in water because of increased
carbon dioxide tension due to cellular activity.
Since bone cells are
relatively inactive, the carbon dioxide tension is low in their vicinity, and consequently the neighboring calciia and phosphate ions become
less soluble and precipitation occurs.
Robinson (23) believes that an
increase of PC4 ions in the zones of ossification is responsible for
the deposition of tertiary calei-a phosphate in such regions.
These
ions are apoarontly secreted by the enzsne rhosphatase through the hydrolysis of the ohosphoric ester
of this substrate.
the red blood cells, the store house
strangely, niagnesiun is the only
ion that
activates phosphatase universally with the exception of callus tissue
which, according to Kuwabara (71), is activated by calciuw.
The inor-
ganic phosphorus of the serta, the phosphoric ester in the red. blood
cells, and phosphatase of the seruw are all higher during the
of rapid grovrth and fall gradually to the adult level.
rl
(60) Ee
4G)
states that phoohatase is manufactured by body cells of inesenchymal
origin, including osteoblasts and hypertropio cartilage cells, and
ic particularly abundant in the region of calcifying cartilage.
Shipley, Kramer, and. iiowland (126) found that calcification took place
when epiphyseal cartilage from rachitic aninals was added to a prepared
solution of inorganic salts.
If these opiphyseal cells had, been pre-
viously killed calcification did not proceed normally.
This was biter-
preted to signify that the live osteoblast tvas necessary to the process
of ossification.
Such an explanation harmonized, with Watt's theory.
(l5) However, after the discovery of phosphatase, Robinson, MacCleod,
nd Roseijieiza (114) were able to bring about ossification by placing
dead slices of racliltic bone and phosphatase in a calcifying medii.
This proved tha' it was the phosphatase, produced by living cells, that
was necessary in ossification.
(46) Kay (67) suggests that cal-
cification is affected by nwnerous factors such as the form of the calci
in the serum, the phosphorus of the blood, the p11 of the plasma,
the parathyroid. hormone, the thyroid hormone, vitamin D, the oa1cia
nd phosphorus intake, the effective acidity end alkalinity of the
food, and the chemical reaction of the intestinal contents.
In addition,
at least one other vitamin and possibly other endocrine glands play a
part in bone forriation.
(79) Ham (46) concludes that the calcii.n con-
trolled by the oarathyroid.s, the ionic calcium, and the calcium in the
bone matrix are in an active stete of equilibrium at all tines.
In a
recent article Benjamin (7) demonstrated the presence of a calciumphosphorus complex in an artificial solution containing calciLmi phos-
phate, carbon dioxide, end bicarbonate.
This complex was thought to
be similar to the uiltrable, adsorbable calcium-phosphorus complex in
serum.
She suggests that ossification may involve the adsorption of
39
the caoiimi-hosphorus coriolex by cartilage in the region of the
opiPhy3eal junction.
kobinOontS theory of bone forr0iation is, perhaps, the iost convincing
ewlanatjon of bone fomation.
23) It involves the lLberation of an ox-
cess of phospbate ions fron the rod blood coils by the enzyme phosphatase
in the region of bone forroatioxi. These ei':cess ions unite with the ca].-
citmi of the serun to Lorim insoluble tertiary calcia phosphate.
7hile
muoh has been learned about the calciiu and phosphorus of the blood in
its relation to ossification, more still remains to be discovered.
docker et al
(s)
found tho± the bones of lactating cows Led rough-
age raised on acid land were iieing deileted of calciimi to such an extent that they were weakened and easily broken.
1hn bonemeal was add-
ed to the diet, roinerals were again stored in the skeletons until the
shafts of the bones hecarac above average in strength. Karshan (68) produced severe rickot in rats with a diet containing a Ca:
P ratio of
7.27. Henderson and 7eakley (51) reported that altering the calciixm:
phosphorus ratio did, not affect the skeletal developneiit of calves until either the calciun or ohosphorus intake was markedly decreased.
hciraers and 6iuts (112) obsexed that increasing the calcium and phos-
phorus in the diet of growing pigs above a certain point did not increase
the percentage of the ash, although it did increase the total weight of
the bones. Maynard et al (89) found that adequate protein was necessary
to bring about optal calcification of the bones of growing swine.
It seeros reasonable, then, to conclude that optiroal skeletal
development is, first of all,.. deoendent on an adequate diet. To what
40
extent the pork and beef on the market have been deficient in the
essential food factors is open to question.
Bohstedt (16) states
that with the use of practical rations as controls no need has been
found for additional calcium and phosphorus in the diet of farm animals.
Since it is economically profitable to feed animals a ration that will
insure reasonably rapid growth, especially in the case of pork, the
question arises as to what extent the rapid growth of hogs and cattle
is accompanied by optimal skeletal deve1oitent.
Since hogs, more
than beef, are sold during the period of rapid growth, it might be suspected that this factor might affect the composition of hog carcasses
on the market.
EFFECT OF VIT.TIN D
Brown and Shohi (19) used the X-ray on rats in studying the effect
of this vitamin on calcification.
They discovered that. in normal
amounts vitamin P affected intermediary metabolism by dissolving minerals from the shafts of the bones and depositing them in the ends;
furthermore, that small doses improvedretention of calcium.
However,
with large doses of vitamin D the calcium was dissolved in the blood
in such large amcurrs that the mineral was eliminated in the urine in
order to re-establish mineral equilibrium in the blood.
VABIATION OF CO1vPOSITION OF bONE
Diet.
It is a generally accepted fact that the ratio of calcium
to phosphorus in the bones remains constant regardless of the proportion
of these itinerals in the diet.
tion takes place j
however, the extent to which ossifica-
dependent on the adequacy of their intake.
(140)
(57) Maynard at al (89) found that low calcium in the diet of hogs
41
resulted in poor skeletal develoent, although growth was not particularH rover, Horn (62) observed that pigs on very low caleiwa
ly retarded.
showed clinical sptoms along with altered bone composition.
Mathews
(aa) gives analyses from Roloff which show a great increase in the calciwii content of the shoulder blades of growing dogs on a high calcii. diet
in comparison with those of does that had been fed on a diet low in Ca].-
oIn.
Templin and
teenbook (140) found that the bone ash of adult rats
was reduced on a diet restricted in calci'-a.
Henry and Morrison (52)
refer to a study made by Hart, McOollwn, and Hiphrey in which a cow on a
ration deficient in calci
gave more calciun in her milk than she conswi-
ed by an amount that, for the period tested, was equal to one-fourth of
all the calcium in her body.
Uechdel et al (4) have observed that rickets
in calves was associated with a low Percentage of ash in the bones.
roo1e et al (18) have reported that the carbonate rather than te phosphate of the bone was reduced on a diet poor in inorganic constituents.
Rate of Growth.
Outhouse and Mende]. (107) recently discovered that
the more rapidly growing rats have skeletons with higher water and lower
inorganic oontons than the more slowly growing controls.
.e.
nal:rses made at the Missouri Experiment station on 33 beef
animals ranging from birth to four years signified that the ash of
calves was constant, but that the caloiwa, phosphorus, and magnesia
of the older animals tended to increase with age.
(54) Hess, Borlinger,
and Jeinstock (53) found that the bone ash of rats became higher in the
older animals.
In a comprehensive study, Kruger and Bechdel
a slight tendency for the ash of calves to increase with age.
75) found
42
Sex.
Ho1mes, Pigott, arid Moore (58) found that bi tEe tibiae of
chicks the ash of the males at three weeks was greater, while at six
and nine weeks the tibiae of the females showed the higher ash content.
Harshaw, Fritz, and Titus (48), in an X-ray shadowgraph study, observed
earlier calcification of the epiphyses of the tibiae of the female chickens.
Hainett (47) found that the ash content of the female rat vras high-
er than the male.
Figor (7) noted that, at three years, there is a
similar ossification of the epiphyseal cartilage in bulls, cows, and
steers, but that in older bulls ossification proceeds more slowly.
These data conforz with the well-1movn fact that the female of the species matures more quickly than the male.
The much discussed effect of
pregnancy and lactation on the skeletal integrity aro too well
to warrant more than the conent that animals are usually not marketed
as a source of food when pregnant or lactating, although they may be
recovering from either phase.
Breed.
io evidence of the effect of breed on the ash content of
the bones of hogs or beef has been encountered in this study.
ing with chickens, however, Harshaw, Fritz, and Titus
In work-
(48) report that
the epiphyses show earlier calcification in Leghorns than in Rhode
tslands.
Variabilir of Parts of the Sajee Bone.
Kruger and Beohdel (75)
report that the ribs of calves are the first part of the skeleton to
be affected by rickets.
These investiators also found that the complete
rib was more satisfactory for the analysis of calcii
than a cross se
section of the bone.
To surmiarize:
diet, rate of growth, age, sex, breed, and method
43
of zoaipling nay affect the calcita content of the bony cuts of beef or
pork.
In this study we are interestod in whether the difference in tie
composition of the bone affects the extent or the ease with which
ea1chn js freed from -the bones in the cooking process.
In other words,
is calcii. given up by the growing ends more readily than by the more
nature central sections of the rib?
Furthermore, does the bone of
rapidly growing enimals, such as young pigs, yield calcin more
readily than the adult bone of beef?
T'nese are unsolved problems.
44
C ARTILAG
FORMATION
TD CALCIJ COHTEKT
One type of cartilage is permanent while the other type is the
forerunner of bone.
Ham (46) gives this interesting version of the
origin of these types.
Osteogenic cells well supplied with blood form
osteobla5ts that ultimately produce adult bone cells.
But in the absence
of a good. blood supply the osteogenlo forerunner differentiates into
cartilage cells which persist for life.
calcium content of either type.
We have little evidence of the
Harshavt, Fritz, and Titus (48) refer
to the fact that St. John and Kemp found the calcii.ri of epiphyseal
cartilage much more susceptible to change in rickets than the bony
diaphyses.
Schmidt (119) states that the calcium content of costal
cartilage has been found to be nearly the same in normal and rachitic
children which, incidently, denotes that delayed ossification is not
due to the inability of cartilage to fix calcium.
He also found slight-
ly more calcium in the zone of bone formation than in resting rachitic
costal cartilage.
Lubosch ('TB) has found. that, in lower forms of life,
there are distinct deposits of calcium in the cartilage before ossification can be detected.
The Encyolopoedia Britannica (36) states that
there may often be deposits of lime salts in the matrix of txyaline cartilage especially in older anLuals or in deep layers of articular
cartilage where it is attached to the bone.
Burger and Schiornica (21)
found a large and significant increase in the percentage of calcium in
the costal cartilage of 68 individuals ranging from birth to 85 yearS.
Froudenberg and Gyory (40) observed that the calcium ion (but not
45
the pLosphae ion) is bound by cartilage.
In a study of the chemical
changes during the healing of fractures, Sohwars and Herrmann (121)
found that cartilage contained 16 to 17 per cent of calciisa, while bone
contained 23 to 25 per cent.
This datim :as interpreted to signify
that ca1cia was first laid dawn in organic comb.nation, and that its
union with the
hosphate ion occurred subsequently.
Oikawa (105) found
that the articular cartilage of the whale contained 2.4$ per cent ash.
Tinters (150) reported the ash content of oig's nasal cartilage at 10
per cent.
Oilbor (131) found 4 ocr cent ash in air-dry cartilage frii
rabbit's ear, 3 ocr cent of which was calcitn.
It see
reas:'rable to
exspect the calcitua content of the more firm costal cartilage to he
higher than the less finn cartilage of the nose and ear.
ilathews (88)
refers to Burger and Gies who give 6.8 zer cent as the. ash content of
air-dry costal cartilage.
TilE 0J(TIhTGE OF
In the spareribs of this study, the cartilage, which was cooked
with the meat and hone, was allowed to remain in the samples to be
analyzed.
This included the eiphysea1 cartilage in the zone of growth
catilage
at the sternal junction of the ribs together with the hyal
e do not
of the adjacent part of the siornln which never calcifies.
lciow what happens to the ca1cii-a of this cartilage:
whether it is
dissolved and conswoed with the meat and solution or whether it is
discarded with the cartilage.
It would seem that calcit
easily removed frorL cartilage than from bone.
might be more
Silber (131)
found in working with cartilage from the rabbit's ear that 90
per cent of the minerals was leached out by water in the course of
three weeks.
This is no index of the minairL time it took to reMOve
the calcii or of the extent to which it was removed.
The fact that
McCanee, Sheldon, and Widdovrson (91) were able to dissolve the rnexim
yield of ca1ciri from the chopd bones of veal by soaking them either
in cold water or in the solutionduring one ouS cooking suggests
that the calciti would probably be largely removed from the cartilage
sin the cooking Process.
Thus far we baow little about either the
quentity of calchrt bound by cartilage, or the uniformity of its
distribution in cartilage, or the extent to which it may be dissolvod
by the cooking solution.
S.
47
EXPERflflNAL
fIE ?ROBLEIi
Since one serving of a Chinese dish of meat and bone liovm as
°sveet sour spareribs
only 0.0275 gr
was found to yield 0.5504 gram of calcit,
of which was derived from the cooking solution
itself, it was thought worthwhile to apply the principle of acid
cookery to American dishes of meat and bone and, analyze them for
calcium as a basis for determining the desirability of mOlifying our
culinary procedure in the preparation of certain cuts of meat.
A. SAMPLING OF .iiERI,LS
The nutritional history as well as the age at which hogs are
marketed is slightly affected by seasonal variation.
Spring hogs are
likely to have more green food and possibly more milk and less grain
than fall hogs.
There is a tendency to market hogs at a smaller size
and, consequently, at a younger age during the heat of mid-simmer, which
'as when these analyses were made.
The six ribs in pork "spareribs"
just preceding the four posterior ribs was the cut of meat used in this
experiment.
Each rib was divided into four equal pi.ces, approximately
one to one and one-half inches in length, and alternate pieces from
rib one, three, and six from both sides of the se animal were used
in making up two samples.
Alternate pieces from the remaining ribs
were used in making up the other tao samples.
The meat, bone, arid
cartilage were weighed together after the excessive fat had been removed.
As soon as the meat had been slightly browned in enamel 1ttles of
like size and shaoe on an electric stove the cooking solutions wore
added aiic3. the covered solutions cooked at aanroximately 97 degrees
Centigrade for one hour.
The corn starch mixed ''ith 15 cc. of water
was then added and the heat turned off as soon as the solution thickened.
Twenty rainutos after the corn starch had been added, the bones
were removed from the meat with tweezers.
The bones were thoroughly
rinsed five times; and the rinsings were returned to the kettle.
As
a check on the equality of their division among the different samples,
the weight of the bones of each sample was taken directly after their
removal.
The' contents of each kettid, with hot rinsings, u±ts trens-
ferrod to a large evaporating dish.
B. P
.J.c.hTI0iT OF
:?LES 9CR
xLYIS
The procedure following evaporation of the liquid over the steam
bath depended on the treatmont of' the fat in the sample.
During the
exueriments in which fat was extracted in Soxhiet, each sample, after
being dried in an eleotrio oven for four or
Fahrenheit, was, transferred to several bags.
hours at 100 degrees
The residues of these
bags were extracted far four hours in alcohol followed by four hours
of extraction in ether.
a radiator at
hach sample was then thoroughly dried over
5 to 40 degrees Centigrade, weighed, and reheated to
constant weight.
If eh'Uraotion in
oxh1ot was omitted, after the
liquid had evaporated amost to dryness, the contents of each evapor-
ating dish, with rinsins, was transferred to alive inch ashing dish
of imown weight.
degrees Fahrei'theit
E&ch sample was d±ied for four or more hours at 100
It
s then thoroughly washed with other, and the
'at and other were reweved through ushless filter paper.
49
Later the filter taper was returned to the samo and its dry weight
sub-Uracteg from the constant weight of the dry samolo.
In the lean
sooles all fos of extraction were omittod.
As soon as they wore dried to ccnsta_'it weight in the electric
oven, the samples were decomposed in an electric muffle furnace until
a gray ash was obtained.
In the first experiments the sarmies wore
asked at 700 dogroos Centigrade, but in subsequent ashins 450 degrees
was found to furnish
after six to
uffioient heat.
During all the le±or'experimen-Us
we1ve hours of asking, the sanples were cooled and 5 cc.
of concentrated H04 was added under cover to each sample.
The sonple
was then heated over a flame in the hood until the ftmies were driven
off when the dish with th
sanele was returned to the furnace and heated
The purpose of this cd treatment was to promote oxid-
to a gray ash.
ation of the sample at a lower te::ierature and avoid any fusion of the
calcii with the dish.
most imortant.
The initial ashirg
rocedure was considered
Then the sample started to smoke the oven was turned
off for at least One hour and then turned alternately on and off until
asking had proceeded beyond the stage where calcium might be mechanically
carried off.
calci
!m insignificant result was obtained from an analysis for
made on the sawcle obtained from a carbonate fusion of the acid
imzoja;hlo residues of the ashes from 18 analyses together arith any material that ini:ht have bean derived from the dishes.
This signified
that calcium was not being lost either in the ash 0f the samples or in
the formation of insoluble
ilicatos -:yith the dishes.
50
Ufl
Crm-r
U. £
-?-n
U :_Lj)
a_CrrJL. -;
hineie Vine:ar.
soon disccverod that duplicating the
It
-Jhinese re-ie in aieouzits did not croduce a cooking solution irith a
ro1ity corre
(cs).
oning to 0.15 N, the acidity obtained by Niss Hoh
The loH rocult, Thich corresponded to 0.03
due to She use of a
eaker zinvcle of vinegar.
-T,
-;as apparently
Thereafter the total
titratable acidity C± each purchase of Chinese vinegar :as detorejinod
and, the recipe varied to keep the cooking solutions 0.15 N.
nles of Chinese rice vinegar testing 0.23 N, 0.
Five
N, 0.17 N, 0.40 N,
arid 0.2-1 N-ero used in the course of this study, the fifth being a
raic-:ture of the re:aaaneor of four curehases.
Soybean Cauce.
The soybean sauce, :ith a basicity corresponding
to 0.366 N, required acid to neutralize its effect and also to
an aoidi5' in the cooking solution corresponding to 0.15 N.
sauce
roduee
The soybean
ye the entIre cooking solution a basiiby oorrespcndng to
0.0.Loc n calrj,auea thus:
- basicity of the solution due to the soy'been sauce
0.388 - h-.sicity of the soyccan sauce
cc. of soybean sauce used in the recipe
10.
total cc. of the cooking solution
235.
X
0.388
:
10
:
X = 0.0165
Thus, to give the cooking solution an acidity corresponding to 0.15 N
additional aold :ias required to counteract the basic effect of the soybean.
-
The acid reauired vras the sa of 0.0165 N, the anount necessary to
51
eutra1ize the soybean sauce, and 0.15 N, the de6ired acidity, or
0.1665 N).
0.1665 N (0.0165 N + 0.15 N
The deternination of the
arnount of acid required was calculated thus:
x
number of cc. of acid required
1665 N = normality required to produce a cooking solution with
a normality corresponding to 0.15 N
N
235 cc.
normality of sanple of Chinese vinegar
volume of the cooking solution
0.1665
N
X
235
Vihen the vinegar was used in the recipe without soybean sauce less
was required to make the solution 0.15 II thus:
merican Vinegar.
0.15
N :: X : 235.
The pure cider vinegar which was used through-
out the study tested 0.8 N and. ;as 4.9 per cent acetic acid.
Potassium Pern.anganate.
Potassium
*
erraanganate testing 0.0955 N
was used. in the preUniiary exnerinents only; a solution which tested
0.0916 N throughout was used in all of the remaining analyses.
Other Reagents.
In most oases reagents were prepared in amounts
sufficient to last during the entire period.
Distilled, water was used
in cooking, in the washings, and in transferring the samples.
* Heinz's bottled cider vinegar purchased from a local grocery store
52
D. CALCImI DETER.IIILTICii
.
modification of the volumetric method of calcium analysis as
given, by Mahin's Quantitative
nalysis was followed.
(82) The procedure
as outlined below is similar to that used in the Experiment Station
Research Dearient of the Oregon State College.
Calcium was precipi-
tated as calcium oxalate Cac904 by amionium oxalate (NH4)2C204.
10 cc. of water and 20 cc. of concentrated IICL were added to the ash,
which was then carefully heated to boiling and gently boiled under a
watch glass for at least five minutes to expel the carbon dioxide.
The solution was then filtered into a 250 cc. flask.
The dish was rinsed
twice with 5 cc. of HOL followed by one or more washings with hot water.
After the filtrate was made up to volume and thoroughly mixed, aliquots
of 50 cc. each were drawn out with a pipette, which had been checked
for accuracy.
Each aliquot was boiled gently in a covered beaker with
50 cc. of watar for 5 minutes.
One drop of methyl red was added and followed by drops of (NH)OH
until the reaction was basic.
Five more drops of acetic acid, were added
after the solution just turned pink in its presence.
hen the covered
beaker vras heated aL'nost to boiling, it was removed arid 25 cc. of re-
cently filtered, saturated (rni)2C2o4 were added drop by dro, with constant stirring.
The beaker was then placed on a steem 'bath for three
hours or longer after which the calcium was tested for complete
precipitation by a drop of (im)2c2O4.
The filtering was done in a Gooch crucible with a filter of
purified asbestos that had been thoroughly rinscd with distilled water
53
along with the beaker end cover glass.
The precipitate was first
washed with 80 cc. of 1 per cent (iH4)2C204.
three crucibles of water.
It was then washed with
The Gooch Was transferred to a beaker
where the Ca20204 was dissolved in 55 cc. of water and 20 cc. of
dilu;e H2SO4.
After being heated to boiling, this mixture was held
at 7. to 80 degrees Centigrade on a steam bath during titration with
standardized permanganate, approximately 0.]. N, which was added drop
by drop while the solution was kept in continuous motion.
The first
flash of pink which persisted for fifteen seoonds was the end point.
Reaction:
CaC204 + H2SO4 = GaSO4
2ICAnO4
Calculation:
a.
..
5H2C204
1 cc. 0.1 N
ho. cc. hT.1n04 used
.
E2C204
3H2304
iinO
K2$b4 42MnM4
10002 8H0
0.002 grn of calciui
N of IOAnO4XO.002 gram
oa1ci
in 1 aliquot
0.1 1I
b. Ca1cii.
in 1 aliquo.t X
rio. of aliquots
total calciia in a sample
The yield recorded for each sample was an average of the results
obtained from three aliquot portions.
Incidently, the results ofthe
aliquots were always in close agreement.
calcit
No deduction was made for
in the reagents, since the permanganate remained pink when
added to the distilled water blanks in amounts of less than one drop.
E. SPARERIBS
standardized by
The Chinese recipe for
Missh (55) gave the cooking solution a total titratable acidity
corresponding to 0.1496 N and 0.1515 N.
The ingredients were used i
the following oroportions:
Pork soareriLs ------------------ 150 to 150
ss.
Cooking solution (total) -------------- 250 cc.
Rice vinegar --------------------------- 75
soybean sauce ---------------------------- 10 cc.
Distilled water ----------------------- 150 cc.
Sugar------------------------------------ 10
ialt------------------------------------ 1
Corn starch ----------------------------- 5
T1.
s.
Cold water (distilled) ----------------- 15 gras.
Duplication of the Chinese recipe with a different supoly of
ingredients, however, resulted in a cooking solution :ith a lower
acidity.
Since the yields obtained in this study were lower than
those obtained by Miss Hoh, it seemed advisab1
original recipe so far as possible.
to duplicate the
For this reason the eount of
vinegar in the cooking so].ution was increased.
The siethod for cal-
culating the eount of vinegar was given on page 51.
ly the compo-
sition of the total liquid of the recipe vrs changed in altering the
basic recipe to compare the effect of the various cooking solutions
on the total caloii
of the scp1es.
The caleirn yield of the different saiaples was calculated on th
55
the hasie of 180 grams of raw saniple.
This procedure overlooked the
small emount of calcitmi derived from the cooking solution.
determinations of the ca1cii
No separate
contents of the various cooking solutions
were made in this present study.
iTover, Miss ioh obtained 0.0275
grants of ca1ciiu in her analysis of the Chinese cooking solution.
Thus, the theoretical yield on the basis of iSO groms exceeded the
actual yield in samples of less then 180 grams by a fraction of the
derived from the cooking solution.
calcii.
In a study of this type
such an amount was considered too small to be of any practical significance.
It is one problem to detormaine whether acid cookery is justified
by the inoreised yield of calcium in bony cuts of meat.
It is quite
another to prepare a palatable
In order to
aerican dish with acid.
discover whether a serving of pork spareribs prepared with ierice
vinegar in a cooking solution with an acidity corresponding to 0.15 N
could be us3d as a foundation for an edible american dish, vegetables
and seasoning were added.
The ingredients were used in these propor-
tions:
Pork spareribs (meat, bone, and cartilage)- 180 gas.
jerican vinegar --------------------------- 43 cc.
;'rater (distilled) ------------------------- 192 cc.
Sugar -------------------------------------- 15
s.
Salt---------------------------------------- 4gns.
Vegetables:
2 carrots (precooked),
onion,
potato, 3 slices green pepper
56
2his cnbination ..ras sirnered for one and one-half hours.
paste of
.
5 graas of corn starch and 15 cc. of water nas added and a11ed to
boil before the dish was served.
The product was considered, palatable to those who do not object
to Itho acid flavor with meat.
The pH of the solutions, which was
detoxnined by the quinhydrone electrode, follows:
Chinese cooking solution (raw) --------------------- 4.9
Cooking solution with
serican vinegar and soybean
sauce ------------------------------------- ---
4.2
Chinosevne:ar ------------------------------------ 4.1
bscrican vinegar ------------------------------------- 3.5
:ith the hydrogen oleetrode
iss Holi obtained a pi value of 3.2 to
3.24 for her s'wl3 of Chinoc vinegar.
he diversity in pH in the
two Chinese vine:ars may ho duo to the methods of measurement as well
as to d.iffmet )ro: rwds of the to amule.
ity Of the meat fish pre
hile the total acid-
red mifh Chinese or mmrican vinegar may
be the seme, the p11 of the solution with fmerican vinegfr will be low-
er than the solution with Chjnese vinegar and, conseamontly, the
product aontaining the merican vinear mill be more acid in taste.
J3iCF kdCIJ 7TBC
In crd
to study the conuarative effect on the calcitw yield of
aoid versus mater cookery in a similar cut of meat froi a different
species of animal, short ribs of beef mere preoared with and without
acid according tO the basic recipe on page 5 of this study.
marl:eted as such at
n earlier age than is pork.
Beef is
Since beef contains
57
larer omounts of oonnecbive tisouc, it vas necos
:ch longer than pork.
invigation;
ry to cook it
o new factoro were introduced, in
Thus,
his
The d±fferenoe in the age of the aniials of the two
specieS and the difference in the cooking tine of the pork and beef.
Ineidoily, more concentrated acid was used with the pork than with
the beef.
Fire ribs frori the cut,
short ribs of beef", were each sawed into
fourths of apro:doiately one and one-half inches in length.
oboes from each. rib were used for four sanles.
iternate
fter the bones had
been weighed separately from the meat (with the poriostetori that could
be
eoied or scrawed from the bones), both were brorned together in an
enoro1 kettle.
Then the cooking solution was added, and the covered
minture allowea to smrnier on an electric place at P7 degrees
Conijrade for three and one-half aour.
made with the smp1c2 from an:kaal
was followed.
,
gx'braetion in Soxhict was
but later a differenb procedure
The tendency of the beef scziples containing fat to ignite
during the asking was uuoh more evidont than with pork.
It was neces-
sary to avoid ignition because there mas danger of calcium heia
mechanically crriec1 off in the
raoess.
The most practical method
cclved was to cool the kettles and contents in the refrigerator
until the larger part of the fat could be skimmed off. 'Phis fat was
vrahed three tines in distilled 'rater.
The washings were returned ot
the moat and solution, which was then transferred to an evaporating
dish and dried before ashing.
58
RESULTS WIiE SPARERIBS
Results are discussed under each of the different factors that
might be found to influence the calciun yield.
Since the total calcium
was so variable, particularly from different animals, it was thought
advisable to designate the particular animal front which the sample was
secured.
The nuntber in the left hand column of the tables under the
caption "animal" refers to the number of the pig from which the
sample was obtained.
analysis.
The 14 pigs wore numbered in the order of their
The samples included meat with bone and adjacent cartilage
unless otherwise stated.
The cartilage, which probably would not be
classed as "edible") was not removed from the sample but was analyzed
with the meat and solution.
THE EFFECT OF FAT EXRACTION
In order to study the underlying factors in the production of the
0.5594 grant of calcium obtained, from one serving of "sweet-sour-spare-
ribs" in a former study,
seemed desirable to standardize the technique
in the preparation of the samples for analysis.
As an aid in deter-
mining whether the expensive and time consuming extraction in Soxhiet
was necessary to the accurate determination of calcium, samples of the
dish
prepared from the same animal were analyzed
in duplicate.
Two samples were extracted in Soxhiot.
The other two
samples were rinsed twice with ether, which dissolved the excess fat.
kfter the dissolved fat had been filtered off with the ether, the ashless filter paper w,s returned to the dish and ashed with the dry
material.
Table I gives the results from these four samples prepared
59
by the Chinese recipe with the cooking solution of en acidity
correseondin
to 0.1 II.
TABLE I
THE EFFECT OF FAT EXTI&CTION
Aveage
weight of
Raw Spareribs
nima1
3
Fat
Extraction
(gms.)
Calcii Ca1eii
(gm.)
(gn.)
0.348
180
0.238
So:thlet
0.293
0.286
O.28
0.255
The variabilftv of calcium in the two samples in which the fat
was not extracted in Soxhle-t may be due to the unequal distribution of
the available calcium in the scricles.
The average yield fran the two
methods agreed closelj, slihtiv in favor of non-extraction.
These
data were taken as evidence that extraction in Soxhiet is not essential
to the recovery of the calcium in the ash.
rfj
conclusion is further
substantiated by methodz given in Allen's Canercial Organic Analysis
(97) for asking cheese and neat.
The directions favor the removal of
the hulk of the fat in cheese by washing the dry sample once or twice
with ether, but give the alternate method of heating the cheese over
a burner until the fat is destroyed before ashing at a low red heat
in a muffle furnace.
llen's test states that, after meat has been
dried in the oven and carefully charred, it may be ashed slowly over a
Fletcher burner at a l
heat.
Thus, it would secm that extraction is
60
Extraoi;ion in Soxhiet
not considered essential for accurate results.
vras used only in the earlier analyses of this study and is designated
in all the caloiin yields followed by en asterik.
TH EFF:G: OF 0IFFEiElJT ::CiJThS OF VIyEGR
Asone basis for coirting the effect of different acidities of
the cooking solution on the yield of calciwn in the soniples, spaeribs
pretjared with -two concentrations of Imerican vinegar were analyzed.
T:BLE II
OF DIFFREHT :i.IOUNTS OF VLJEGlR
TK
Oooking
Solution
;nimal
1
(ce.)
250
mericen
Vinegar
(cc.)
45
eiht of
Raw Sproribs
(gins.)
180
23
Calciin
(gin.)
0.107
0.092
The slightly greater yield of 0.107 grern fra the more eoncntrated solution in comparison with 0 .092 groin of calcium from the less acid
solution was not sufficient to ju-tifi the more acid flavor of the
foner so.ution.
Those results indice±e that the total acidftv of the
cooking solutior., at the two levels tested with rnoricon vinegar, is
not a potent factor in affecting the total calcium yield of cork
SDarerjbs.
TU EFFECI OF DIFFRENT ACIDITIES
The yield of calcium from spareribs cooked with two dilutions of
nierican vinegar was much lower than the 0.5504 grain of oa1cin per
serving obtained in a Cornier investigation.
(55) The object of this
61
entire study was to discover whether the factor, or factors, responsible
for the high caichni yield in Chinese Hsweet_sour_spareribsH could b0
applied to kierican meat cookery.
As one step in the solution of the
problem it seeied advisable to prepare a serving of Chinese spareribs
and analyze it for calcii..
The acidity of the Chinese recipe,
as prepared by Miss Hoh (see recipe, page 54), gave a total titratable
acidity corresponding to 0.1496 and 0.1515 N to the cooking solution.
Repetition of the Chinese recipe with another supply of ingredients,
however, resulted in a cooking solution with a total titratable
acidity corresponding to 0.06 II.
This inconsistency was attributed
largely to the difference in the acidities of the two samples of
Chinese vinegar.
Since the total oalchn was so much lower than
that obtained by Miss }ioh, it seamed worthwhile to reproduce the
Chinese recipe in so far as possible.
Therefore, the vinegar was
titrated and used in an amount calculated as sufficient to duplicate
However, -the basicity of the soybean sauce
the original acidity.
had not been taken into account and the acidity again fell short,
giving a normality corresponding to 0.13 N.
Increasing the vinegar
to compensate for the soybean sauce gave the cooking solution a
normality corresponding
o 0.14 N, the acidity which was aoprox-
iated in the remainder of the experitonts.
The following results
show the effect of three levels of acidity on the oalcitr yield.
62
TABLE III
TKE EFFECT CF DIFFERENT ACIDITIES
Aidity
Animal
of Coohiiig
Solutiori
Raw $uareribs
gs.)
2
0.06 N
180
3
0.13 "
ft
U
Caleiix'.
CaIci
er 180
(gm.
0.313
0.348
It
II
U
II
fl
u
0.236
It
ft
n
0.254
0 .256
Average at 0.13 N
5
0.147 N
6
ft
10
0.289
175
ft
-
U
Average at 0.147 N
0.147
0,151
0.148
0.177
0.2595
0.2595
0.3326
0.333
0.230
The senpies cooked in solutions of an acidity corresponding to
0.147 N varied more widely in ca1aii content than the average yield
at the three different concentrations.
Results from the cooking solu-
tions of an acidity corresponding to 0.147 N ranged from 0.151 to
0.333 gram of total ca1cii; while the averages from the cooking
solutions corresoonding to the normalities of 0.06, 0.13, and 0.147
gave calcium
resoectively.
in the following amounts:
0.313, 0.289, arid 0.230 gram
Furthermore, the average yield from each degree of
acidity decreased with the increased concentration of the acid.
However, it may be noted that the ran-e in yield of samples from
63
diffront animals is greater than the range in yield of the samples
frcm the same animal.
Thus, the calcium from different an1s ranged
from 0.151 gram in animal fiu'e to 0.348 gram in animal three, a differ-
ence of 0.193 gram.
The range of four samples from animal ten is 0.074
gram or the difference between 0.333 and 0.259 gram of calcium.
Results
indicate that the unequal distribution of available calcium in the
samples from the some a.nL'.a1 and the individual differences in the
samples from the various animals had nore effect on the yield of the
samples analyzed than the total titr:tble acidity of the cooking
solution when it was varied in aciditjez corresponding to O.0,0.l3,
and 0.147 N.
THE EFFECT OF THE LIQUID INGREDIElTS
The calcium yields from Chinese "sweet-sour-spareribs
(lable
III) are greater than the yields from spareribs cooked with dilute .4mer-
ican vinegar (Table TI).
This difference suggests that the the acid-
ity of the cocking solution night not be the only factor in the
Chinesø recipe responsible for the yield of oalciuri.
In order to oceare
the effect of the liquid ingredients on the calcium yield, samples
were prepared for analysis with vinegar and soybean sauce, with soybean
sauce, with vinogr, and with water,
64
TABLE 3:7
TIlE EFFCT OF iRi LI.TJiD PTGIEiJIENTS
Liçuid
Ingredient
Animal
To.a1
.eight of
Raw Spareribs
Ca1ciii
.cidity
(gns.)
(gm.)
Ca1cii.
per 180
Soybea21 and
chinese Vinegar
2
0.313
180
0.06 N
0.275
3oyean
Chinese Vinegar
0.075
water
Soybean and
"
7
merioafl Vinegar
_______
U
0.11
Q.06 Ii
0.147 N
0.17
0.134
0.099
0.076
0.113
0.101
0.057
0.051
185
038T
0.37
U
0.452
227
Soybean
merioanVinear 0.147 N
202
.aer
12
Soybean and
Chinese Vineg
0.147 N
Soyhen
Chinese Vinegar
0.147
j
7ater
hen the liquid ingredients of
from the Chinese recipe with animal
ca1ci
ft
O.36
0.58
Q497
0453
ho cooking solutions were varied
nber twelve, if the available
had been equally distributed among the four samples, the results
in Table IV would have indicated that soybean and vinegar rere
rnative in effect, since the serving with soybean and Chinese yin-
egar gave 0.313 gram of calcin, while the serving cooked with soybean
alone gave only 0.273 gram of ca1cii.
The serving cooked with Chinese
vinegar contained u.ii grorn of calciri, while the serving cooked with
water contained but 0.075 gram of ca1oiii.
If these tendencies could
have been duplicated, results would have indicated that the soybean
sauce was a potent factor in dissolving the calchmi.
hen compared with
the results from a serving prepared with american vinegar and soybean
sauce in a cooking solution with an acidity corresponding to 0.147 N,
the series again followed the sane trend with the samples from animal
nirnibor seven.
calcii
The soybean, however, seemed much less effective.
The
of the samples from animal nimiber twelve dispelled any just-
ification for the formulation of such a generalization on the comparative effect of the liquid ingredients.
The yields of the samples
The ser-
from animal ninber twelve were astoundingly high in all cases.
iñg prepared with soybean and Chinese vinegar contained 0.37
gram;
soybean, O.43E) gram; Chinese vinegar, 0.358 gram; anr3, most unusual of
all, water, 0.483 gram.
These high results might be attiibuted to a
difference in the composition of either the bone or cartilae or both
in animal number twelve in comparison with the calciis of the samples
from the other two animals.
The fact that the highest yield was
obtained from the spareribs that had been cooked in water might be
attributed to the unequal distrition of the available calcium among
the four samples.
Thus, no comparison of the relative effect of the
liquid ingredients on the removal of calcium from bone could be
deduced from the above data.
i
CCI ?ARISOJ
OF ThE EFFECT OF CISE w
ftRIC:..N VINEG'R
Since the Chinese vinegar is a rice product while American
vinegar is made from apple cider, the question arose as to whether
the two products had the same effect on the balcimi of the spareribs.
In an attempt to discover whether equivalent concentrations of these
ro acids would. have the some effect on the calchei, spareribs cooked
with Chinese vinegar an spareribs cooked ith iaerican vinegar rere
analyzed for calciur.i.
TABLE V
CF CHIE5E AiD i,ricn VINEGIR IN THE C0OKI1'G SOLUTION
THE EFFEC
Variety
Veight of
of
Lan- Spareribs
nima1 Vizioar
(as.)
Ca1cii
Ca1cin per 180
(gn.)
(gm.)
173.35
0.084
0.088
6
158
0.121
0.138
9
184
0.083
0.081
189
0.121
0.115
156
0.456
0.5456
7
202
0.113
0.101
9
184
0.125
0.122
189
0.0999
0.095
185
0.368
0.358
5
6
Chinese
.iaerican
12
Average ofFourSainp1es with Chinese
Vthegar from hree Jiima1s
Average of Five Sip1es with merican
Vinegar from Three Animals
Average of Iwo omn1es with Chinese
Vinear from Animal Thlraber nine
Average of Two 3aap1es with Anerican
Vinegar from Animal Ntnber Nine
The
0.105
0.222
0.098
0.108
a1oiizi yield of samples consisting of one serving of spare-
ribs nrenared with Chinese vinegar was compared with the yield of
seriples prepared with
lerican vinegar at a total titratable acidity
67
corresoondjng to 0.147 J.
the average -'rield of 0.105 gran of calcin
when Chinese vinegar was used in the
reparation of four seings from
three different aniaa1s was much lower than the average rie ld of
0.222 gram ahen merican vinegar was used in five servings from four
different animals.
The range in rie1d of 0.095 to 0.4456 gram of
calcimr from different servings nreoared With american vinegar was
greater than the range of 0.081 to 0.136 gram obtained from different
servings prepared with Chinese vinegar.
This diversity was attributed
more to the individual differences of the animals than to the effect
of the acids in the cooking nd will later be discussed more in detail.
The uneven distribution of available ca1cimi in the samples is the only
ec1anation that can he offered for the great difference of ca1cin. in
the semules from animal nber six.
One sample prepared with Chinese
vinegar contained 0.138 gram of ca1cia, while another sample prooared
with *morican vinegar contained 0.5456 gram.
The average yield of tWO
servings preoared with Chinese vinegar from animal niber niaa was
comeared with the average yield of two servings prepared with Enerican
vinegar from this sane animal.
Results chec.:ed reasonable close with
0.098 gram for the Chinese vinegar product and 0.108 gram for the
nerican vinegar product.
Those data were accepted as evidence that
nerican vinegar was as effoctive as Chinese vinegar at the same total
titratable acidity, and since the fomuer was less expensive and more
convenient to obtain,
aerican vinegar Ya
used in the remainder of
the experiments.
T
CFFECT OF CCY3EI1J
TJCE 11TH CIJIHEE
ID iERICM VIHEG1JS
It seemed desirable to learn whether the Chinese rice vinegar
in combination with soybean sauce could be more potent than mori3an
cider vinegar in cnbination with soybean sauce in its effect on the
total calcium of the samples.
The comparisons vero made in each case
on the basis of 180 grains of raw sample.
TSLE VI
THE IFFEO
OF gCysE
LTO.F, 1ITH cI:nfPSE
Chinese Vinegar and Soybean
n1na1
10
It
iERICAT VINEGARS
Aiuerioan Vinegar and Soybean
Calcium (gri.)
6
TD
Calcjii (gin.)
0.151
0.149
0.177
0.289
0.2795
0.1699
0.333
0.362
0.379
12
Aver
Liintal
Total
for
10
0.2462
0.2159
verage
0.2159
0.2471
The results obtained from four samples prepared with Chinese
vinegar and soybean sauce differed widely ranging from 0.151 to
0.333 gram of calcium.
The six samples prepared with
ranged from 0.134 to 0.362 gram of calcium.
neriean vinegar
Iudividual variation in
the composition of the animals may account for some of those differ-
ences, since the range of calcium of the two samples from anma1
number ten was less than the range of the samPles from all of the animals when either acid was used.
Thus, in animal niiber ten soybean
sauce and Chinese vinegar produe-bs gave 0.2795 and 0.333 gram of
69
calcium, while soybean sauce and morican vinegar gave 0.1609 to
0.362 gram of calcium.
The total
1oiia of the samples obtained from
animal number five agreed c1osey (0.151 and 0.149 gram), although
one sample was prepared with
aorican vinegar while the other sample
was prepared with Chinese vinegar.
The total calcii
of each san1e
from animalfive, regardless of the vinegar used, was much lower than
the caloi'am of the somIDle Prepared with lcnerioan vinegar and soybean
sauce from animal number six.
Nevertheless, the average yield of the
series (0.227 gram) precared with soybean sauce and Chinese vinegar
compared closely with the average result (0.247 gram) from the soybean
sauce and merican vinegar products.
Furthermore, the average calcium
(0.246 gram) of the samples from animal number ten prepared with soybean
sauce and Chinese vinegar compared reasonably close with the average
calcium (0.2.159 gram) of the samples from the same animal prepared with
soybean sauce and
1erican vinegar.
These tendencies were accepted as
evidence that merican vinegar in combination with soybean sauce was
as effective as Chinese vinegar and soybean sauce in dissolving calcium
from the bones of spareribs.
COT.P:I3C
cF
P01P,
g D CTiG Ct Tt' CLCItf YILD
The diversity of results that could not be attributed to the
effect of the cooting ingredients suggested the presence of other
variants in the secr1es.
The vle1d
obtained from the use of the
some recipe on eampics from the some animal (Table I, animal
Table III, animal
10; Table V, animal
3;
6; Table VI, animal r' 6)
all indicate that the method used for sampling was not resulting in an
70
ecual division of available ca1oiin. To determine what factor or
factors in the :eat dish were contributing to tho ea1ci
yield, anal-
yses were made of samples prepared from meat oj, from meat and
cartilage, and from seat and bone.
TABL
C0TTP:I0IT OF MOAT, OQITE,
Composition
of
a1Paw3onole
4
5
4
1Te.-
II
UID CRt[0;:OC C0 J'HE CALCIUM YIELD
Liquid
Ingredients
oybean and
1:.ht of
nareribs Calciun or 180
ns.)
(gn.)
Chinese Vinei'
181
O.7O
0.073
U
150
0.065
0 078
181
0.6829
0.679
0.072
0.072
I
m0 and
:rflace
U
and.
.An.erican Vinear _____80
8
U
U
0.056
0.056
U
1CO
0.518
0.579
181
0.209
0.207
194
0.106
0.099
270.5
0.098
0.065
13
160
0.20.
0.226
14
175
0.123
0.128
U
U
13
at and
4
Oone
and
Ooybo
Chinese Vinegar
Coybean and
nerican Vinegar
S
1?
'
Average of TTeat
0.0755
Averae of Meat and Cartilage
0.346
Averaj1eofOeat and Bone
0.121
It is apparent that neither the meat nor the solution :as
contributing the larger yields, since only 0.073 to 0.078 gran of
calciun was obtained from that source. The yields from samples of
71
meat and cartilage were the most variable and indicated the presence
of an uncontrolled factor of no small importance.
The ealcimn of one
sample from animal minoer eight was so much lower than the ca1oiii of
the sample from animal rnmiber four that the second sample from animal
eight was transferred to a new ashing dish, since it was feared that
the calcimi of the samples was being lost by the formation of acid insoluble
ilicates with the worn dish.
The second yield. from this same
animal was even lower and indicated that calcin was not being lost in
this rnamner.
The 0.679 gram end 0.579 gram of calcia obtained from two
samples of meat and cartilage (Table VIII, animal
4 and 13) were high
in comparison with the averages of 0.227 grain and 0.247 gram of calciinn
obtained from samples of neat, bone, and. cartilage similarly prepared
(Table VI).
On the other hand, the 0.072 gram and 0.056 gram of calcin
obtained from two other samples containing meat and cartilage end also
prepared with soybean sauce and acid were correspondingly low in comparison with the average yields recorded in Table VI.
These data indicate
that the ealoiin content of the cartilage Ira the samples from different
animals is an important factor in affecting the total ca1cirni of the
samples.
From the available data there is no information on the extent
to which calciita is evenly distributed in costal cartilage.
Neither is
it possible to determine how evenly the cartilage had been divided among
the different samples analyzed in this study, since the cartilage was
not removed from the meat before ashing.
A sample containing meat and bone from animal ni.rnber eight was
low in caleia as were the samolos reprd with neat and cartilage.
72
Since the first sample rith meat and bone (a ; s) was so low in
ca1cimi, the second sample from this animal was transferred to a new
dish for ashing to avoid any possibility of loss from the forr,iation
of acid insoluble residues with the worn Darts of the dish.
That such
was not the case is suggested by the fact that the sample that had been
transferred
as slightly lower than the first.
Evidently, the ca1cit
derived fr
either the cartilage or the 'cone of anima]. eight was pracii-
cally negligible, since the meat and solution contributed an amount
approximating the total calciwi in each of the four analyses.
The 0.226
gram froa the sample of moat and, bone from animal nliber thirteen was
the highest sample analyzed, being slightly higher than the 0.207 gram
from animal nnber four.
Both were higher than the 0.128 gram in the
sample from animal ninther fourteen.
Thus, the calcium given up by the
bone seems to be somewhat variable.
With a method of sampling including two factors so inconstant as
the available calcium of the bone and, especially, of the cartilage it
is apparent that results cannot be exapected to agree any more than,
perhaps, to indicate certain trends.
The removal of the cartilage from
the samples before cooking is suggested as an obvious improvement in
the technique.
tt was previously noted that the middle or older sections
of the ribs have been found to contain slightlr tore calcium than the
ends.
For this reason, Krwer and Beehdel (75) found the whole bone more
satisfactory than the middle sections for analysis.
However, in this
study the ends and middle sections of the bones were evenly distributed
among the different samples.
73
THE EE3 OF LHE .WE OF ..HE
OJ
7KZ
CALCIUM
The question arose as to whether the age of' the anal was
affecting the ealciiri of the bone and cartilage.
The only evidence ci'
the age of these aniials was based on statements made by the butohers,
who, unfortunately, were unable to furnish information about the
nutritional history of the axthials.
Data for the youngest pig and for
an average aged pig were assembled for comparison.
containing
Cooking solutions
nierioan vinegar and soybean. sauce were used in the prepar-
ation of the soni1es of meat and bone and those of meat and cartilage.
TABLE VIII
THE TFFCT OF THE AGE OF THE ItMBdAL OR THE CILC IBM
:o
Composition
of
of
Raw Sam1e
:eatad.
11 Days Cartilge
niima1
Height of
Raw Spareribs
Ca1eiii
per 180
Average Yield
per 180
(gms.)
(gm.)
(pi.)
(gn.)
Ca1cii.i
':'.&
7 :.
4 Io. &
iL2s
Heat a±id
Bonej
0.072
O072
0.056
0.056
0.064
160
0.5183
0.579
0.579
207.5
0.098
0.065
194
0.106
180
7 Mo.
7
Results shbvr that there was no storage of ea1cin in the
cartilage of theyoungst pig that. was analyzed (aged 4 months and .11
days), while the yield of calcium from the bones vras also practically
negligible.
The cartilage of an average aged pig of the group
analyzed. (seven months) showed a large storage of calcium.
More
calcium was derived from the sample of meat and bone from the
74
seven monthts eni:ial (0.226 grem per 180 grrni of raw sample) than
from an average of two somples from the youngest pig of the series
(0.082 gram).
Those data indicate that the ca1cii content of the
cartilage as mell
s the available ca1ciin from the bones increases
with the age 01' the aniia1.
TK YIELD OF CJLCIU
RC
bIlE MONTht S A1fl:AL
Since the ca1citt: ci the samples of meat and cartilage or meat
end bone increased
ith
oare of the animal up to seven months in
two Previous cases (ic VII), it seemed, of interest to note the total
oaiciisa of samples of meat, toie, and adjacent cartilage fri a nine
analysed in this study.
month's animal, the oldest
TABLE IX
I1E OALOIUI. FROM j
Liquid
Inedients
-l2
Soybean and
imerioan Vinegar
jIRE L0jTh S
Weight of
aw Spareribs
(gms.)
185
oybeen
American Vinegr
,ater
Calci
0a1cimi
per 180
(grn..)
(gm.)
0.3896
0.379
0.452
0.439
0.368
0.358
0.497
0.483
The extremely high yield, irrespective of the ingredients in
the cooking solutions, convinces one that animal twelve is the most
efficient as a food source of calcium.
Since -the bone and cartilage
of' this animal wore iot separated in the samples, it is not
iOWTt
in what proportion the available calcium was distributed between the
'bone ana cartilage.
The fact that the highest yield was obtained
75
from the sciuple cooked with water, while the lowest yield was from the
sample cooked with Anerican vinegar suggests an uneven distribution of
the available calciwn.
It would seem that the acid should have been
at least as effective as the water in dissolving the calciin from
the bone.
If this is true, the calcliun responsible for the variable
results must have been largely derived from the cartilage, since the
bone was guito evenly distributed among the somples.
From the avail-
able data, however, there is no way of determining the relative amounts
of calchi contributed by the cartilage and the bone.
THE EFFECT OF lIE LII)UID INGREDIENTS OH TIlE MEAT AD BONE WITHOUT
C:HTILAGE
Previous evidence (Table VIII and IX) strongly suggests that
the cartilage, which was not removed from the samples, introduced a
source of variability in the calcii yield.
4ie removal of the carti-
lage in the raw spareribs seemed a desirable nproveime±it in the
technique of sampling.
ocordingly, somples of meat and bone alone,
with no adjacent cartilage, were prepared with the four cooking solutions and analyzed for calchoi.
The purpose of the investigation was
to compare the effect of the different cooking solutions on the
amount of calciii derived, from the bone.
76
TAILE X
TiE EFFE CT CF LhE LIUID Ii REiES 0i
THE MEAT
ID BONE
WIifhOIJT C!LRTII2.GE
\nima1
1O
'I
Weight of
Raw Spareribs
Ca1ciii
Ca1cimi
per 180
(gms.)
(gm.)
(gm.)
173
0.123
0.128
3o.rbean
0.151
0.157
±orioan Vinegar
0.125
0.13
Water
0.054
0.056
Liquid
Ingredients
oybean and
I,merica.n Vinegar
Results from these four samples of neat and bone without carti1a,e show much greater unifonity than the caloitca of sammles from
which the cartilage was not removed.
The fact that the total oa1ci'mt
is low in cornarison with the average results of the samples
repared
with soybean sauce and either vinegar (Table VI) suggests that the
cartilage,
hioh was not removed before the analyses, may have been
contributing calcium.
Table X is taken as evidence that vinegar is
more effective than water in removing calcium from the bones.
The two results of 0.075 and 0.051 gram (Table IV) from samples prepared
with water indicate similar results.
However, the high result with
water from animal twelve (Table Ix) dispelled all justification of
fonaulating any generalization from such diverse results.
The
calcium of the samples from animal rnmier twelve 'aaa so consi.tontW
high, regardless of the cooking solutions, that the yield could not be
attributed to the method of cooking.
It is interesting to note the
similarity of results from, the use of soybean sauce and vinegar, soybean
77
sauce alono, or vinegar alone in the cooking solution.
No definite
infora'ce 'n be made from these data on the comparative effect of
soybean snjicc, vinegar, or soybean sauce and vinegar in combination.
As far as is 1zo.rn, the bones were equally divided among the four
sep1es.
If the series could have been repeated a sufficient
number of tes, it is probable that the comparative effect of the
liquid ingredients could have been shown.
It is regrettable that limit-
ed time did not permit further analyses with this method of sampling.
A STJJPARY CF THE EFFECT CF THE LICJJID INGREDIENTS ON THE CALCIUM
Regardless of the interference of oartilage, sufficient data
would probably reveal certain trends.
For this reason, averages of
the calcin yield from samples prepared with the different cooking
solutions (Table IV, V, and VI) were asaembled in Table XI.
total çalch
The
was based on 180 gram samples Cf ravr spareribs.
TABLE XI
A STJLUIARY CF
:iF
1 CF
HE LITJID Ii
DIth?
Niber
Liquid
Ingredients
Chinese Vinegar
and ovbean
Ixnerican Vinegar
and oybean
of
Determinations
ON NFE CALO luLl
Aerage
Calcium I Calcium
(gni.)
(gm.)
C
0.227
6
0.2471
Chinese Vinegar
4
0.105
American Vinegar
5
0.222
Soybean
3
0.275
3
0.203
0.237
0.163
78
The average yield of 0.237 grom of calcium from ten samples
prepared with soybean sauce and vinegr exceeded the 0.163 gram
yield from nine somois
repared with vinegar alone at the sane
total titratable acidity b
calcium was present j
an amount of 0.074 gram.
the simples prepared with the soybean sauce
and vinegar combination than in the samples
alone.
Thus, more
reci
'itt
tr;ar
A survey of Table V and VI, the sources of th.:se data, dis-.
closes that samples frori. the srme animals were used in sante, but not
all, of the analyses.
Only three analyses from Table IV were available
for computing the average yields of samples prepared with soybean
sauce and those prepared with water.
These results were obtained
from samples front the some three animals.
The reason for the high
averages was due to the fact that one scnple with each recipe was
from animal number twelve.
It has been previously shown that the
yield of the samples from this animal was exceptionally large,
regardless of the liquid ingredients used, in the cooking process.
Nevertheless, it is interesting to note that the calcium yield
was 0.072 gram higher in the samples prepared vdth soybean sauce
than in those prepared with water.
The potency of the soybean in
dissolving calciinii from the bores is only of 'theoretical interest
in .erioa, where soybean sauce is no-U used as a food.
However,
in China the effect of the soybean sauce on the calcium yield has
a practical aspect and is therefore suggested as a problem
possibly deserving ol' further investigation.
79
A
..ThipJ?Y OF RESULTS
ITl1 SPERIBS
1. Fat extraction, in Soxhiet, was no-U found essential to the
complete recovery of the
aloii in the ash of the samples.
2. Different concentrations of american vinegar in the cooking
solution dld not seem-bc affect the total calciuni.
3. Samples were orepared according to the Chinese recipe with the
cooking solutions, at acidities corresponding to 0.06, 0.13, and
0.147 iT.
Results were so variable that no conclusion could be
dravm on the comparative effect of the total acidity on the total
calcium.
4. A comparison of the relative effect of soybean sauce, vinegar,
a combination of the two, or watar as variants in the cooking
solution revealed no uniform results.
5. The
loluni yield was as large 'with krerioan vinegar as with
Chinese vinegar when used. at the same total titratable acidity
in the cooking solutions.
6. Chinese vinegar or kierican vinegar in combination with soybean
sauce in cooking solutions of the same total titratable acidity
is equally effective on the total calcium.
7. The cartilage was extremely variable in calciunt content.
The car'bilar:e from different animals appeared more variable than
the cartilage from the same animal.
The calcium yield from bone
was less variable and lower than that from cartilage.
Only a
low yield of the -botal calcium could be attributed to the meat and
the cooking solution.
8. The calcium derived from bone and cartilage in an animal aged
four months and eleven days was much lower than in an animal of
seven months.
9. The calcium yield from samples of meat, bone, and cartilage of
an animal aged nifle months was exceedingly high regardless of the
cookiig solutions used.
10. A slightly higher yield of calcium was obtained from a sample
of meat and bone, with no cartilage, preared with soybean sauce
than from one prepared with vinegar or a combination of vinegar
and soybean sauce.
Water seemed to have no effect on the calciLmi
of the bones.
11. In samples consisting of meat, bone, and cartilage, an
increased yield of 0.074 gram of caloiin was obtained with soybean
sauce in combination with vinegar above the yield obtained from
samples preoared with vinegar alone.
Likewise, an increased yield
of 0.072 gram of calcium was obtained from samples prepared with.
soybean sauco above that obtained front samples cooced with
water alone.
81
DISCUSSION oF RESULTS WITTI PORK
The Dresence of more than one variable obviously increases
the difficu1t
of' interpreting results.
In this study the
cartilage content maSr have affected the calcin of the scruples
in any or all of three ways.
First, there was no way of deter-
mining whether the cartilage from the same animal had been equally
divided
ong the samples; neither was there any way of determin-
ing whether the ca1cia in this cartilage was uniformly distributed;
nor, furthermore, was there any means of measuring the difference
in the calcli
content of the cartilage from different animals.
The range in results indicates that one variable. or more did affect
the total calcin of the scsaples.
We do not Iaiow what happens to
If the
the calciti of the cartilage during the cooking process.
cartilage is consimied, the calcium that might remain there
during the cooking process would be of' nutritive value.
ny caloi'.rni that would be dissolved from the cartilage during the
cooking process would likewise be consiued.
It would seem that
calcium might be dissolved from cartilage much easier than from
bone.
As previously stated, the fact that Silber (131) reported
90 per cent of the minerals leached out when cartilage was soaked
in water for three weeks does not signify the speed nor the completeness with which the calcium was removed.
However, MeCance
et al (91) found that the maximum yield of calcium was obtained
from soaking chopped veal bones in water for one hour.
It seems
reasonable that calcium might be dissolved from cartilge in at
least as short a tje as front bone.
The dry weight of the meat included the adjacent cartilage.
Therefore, these weights were not considered significant, since
meat and cartilage differ in chemical composition.
Furthermore,
the weight of the ash was discarded, since the samples were not
ignited to constant weight for fear of forming insoluble oalciimi
compounds with the dishes.
Consequently, the moist weight was the
only means that remained for coTrmcrison.
Although this weight
may vary in moisture content and, cerhaps, oven more widely in. fat,
it should be of practical significance in the interpretation of
such data.
The dietician is interested in the amount of calcitn
that can be secured front a certain weight of neat (as purchased
in the butcher shop) cooked in liquid, rather than the cmount of
ealoitmi that can be derived from a certain weight. of dry or ashed
material.
Another variant in the sampling, apparently of less importance
on the total yield of calcium, was the division of the bones.
Since the bones were not weighed separately from the pork in the
rw state, there :ras no proof that they were equally divided among
the different samples.
The cooked bon:s were weighed after their
renioval from the cooking solutions, and, the weights of the bones
from the different samples were compared.
These weights, which
were not included, since they did not seem to add anything to the
study, usually agreed within a few grams.
This, however, does not
furnish evidence that the bones decreased equally in weight during
83
the cooking process.
Since several factors were involved in the
equal division of the raw spareribs, it is possible that these
uncontrolled variables were largely responsible for the range in
results.
The influence of age, or possibly nutritional history,
or both on the composition of the bone and cartilage of the different
animals may have introduced additional variants.
Furthermore,
while every attempt was made to keep the cooking solutions at 97
degrees Centigrade during the cooking period, slight changes in
temperature did occur, which may or may not have had an effect on
the total caloluit.
Even the length of the cooking period may have
varied slightly.
Because of the uncontrolled factors IiiUc1i data
may not be of great significance.
this thesis
]Eiowever, the yields do give an
idea of the range in calcitmi that can be secured from bone and from
cartilage by cooking them with water or dilute vinegar.
Further-
more, the large ntber of analyses on fourteen different animals
reveals certain trends.
The fact that in a previous study one
serving of "swest-sour-soarerib&' did give a high yield at calcirni,
while the analyses in this present study have given a wide range
of results, should not detract frem the authonticil;y of this present
Study.
The procedure in sampling, the liquid ingredients, the
cooking and analysis procedure may have differed, to say nothing
of the individual differences of the animals purchased at a season
when pigs, on the average, are marketed at an older age.
would seem worthwhil
It
to continue the investigation using older
84
xiima1s, since this study suggests a higher yield from that
source.
If the procedure could be such that high yields could
be more oonsitently secured (provided this form of calcium is well
utilized by hinan beings), bony cuts of meat prepared with liouid
would seem a most desirable cheap source of calciii to include in
the diet, particularly for those whose supply of milk is limited.
RESULTS JITH BEEF SHORT RIBS
The effect of 000ki
with water or acid was studied on a
similar cut of meat from a different species of animal in order
to compare results with those from pork spareribs (page 56, 57).
The calcium obtained from beef short ribs cooked with w:ter or
with dilute vinogr is given in the following table.
T&I3LE XII
CALC L[JM YIELD FR1 BEEF SHORT RIBS
T}
weight of
Cooking
Solution
Müma1
(is.)
(cc.)
X
ater
Vinegar
180
35
X
water
430
X
hater
Vinegar
Y
Vinegar
395
35
395
35
7ater
Y
tater
Raw Smp10
Meat
225
Bone
(gnz.)
Fat
Extraction
55.5
Soxhiet
57
58
69
430
72
(1.)
0.159
-
O. 159
0.158
-------
0.179
0.130
No explanation is offered as to why the ca1oiia from the sample
cooked with water (nima1
prepared with vinegar.
x) was as high as from the two sls
In all the later analyses with beef, only one
of which is included, the samples prepared with vinegar solution had
a slightly higher calcium yield then those prepared with water.
The results, not recorded, were discarded because a loss of calcium in
the ashing process was suspiciolled.
This possible loss was attributed
to too rapid combustion of the samples because of excess fat.
Since
there is no data on the calcium content either of the vinegar alone or
of the meat and cooking so].ution prepared without bone, no statement
can be mode on th
bones.
effect of water in removing the calcium from the
The calcium from the bo:ie dust of the sawed
a variable to ho recognised.
jeces introduces
This dust would probably be ingested
with the meat regardless of the method of cookery.
The absence of cartilage in the soples and 'the greater uniformity
of the bones due, Derhacs, to the more advenced age of the animals
are
Suggested as possible factors that may account for the more consistent
yields from beef than from pork.
Although the cooking time for the beef
was much longer than for the pork, it is to b. noted 'bha-b the additiox
of vinegar to the cooking solution apoared to increase the yield of
calcium in the oork much more than in the beef.
This comparison is
made only with pork somoles devoid of cartilage.
MoCance,
neldon, and üddo-,vson (91) found that the additIon
f a
small emount of vinegar to a cooking solution of water did riot increase
the calcium yield from chopped veal bones.
They suggest that the collagen
and other orotective colloidz that encase the calcium phosphate may act
as buffers and thus prevent the weak acid from having any appreciable
effec-b.
The yield of -ben milligrems of calcium from one pound of bones
cooked in either one liter of water or very dilute vinegar is low.
This ineaer yield is in agreement with that obtained in this present
study from young pork and recorded in Table VII.
Possibly, the younger
animals of both species have less available calcium in their bones than
the older ones.
This study suggests that the calciun yield of older pigs
may be greater than the yield of younger ones.
The concentration of the
87
acid used was less than with pork, although it was as high an amount as
was considered palatable with beef.
Apparently, vinegar is such concen-
tration is not worthwhile with this method of preparing beef.
This study offers no direct proof that cooking with liquid inhowever, the size
creases the oalciva yield of the meat end solution.
of the yield suggests that water nay dissolve some calcium from the
bones.
Soaking the bones before or after cooking in water or dilute vin-
egar is suggested as a method of increasing the ca1ciu yield.
MeCance et al (91) obtained the rnaximu calcium from chopped veal bones
by soaking them for one hour in water at room temperature.
the two samples cooked with vinegar (animal
The bones of
x), after being removed
froift the cooking solution and washed, were each placed for six days in
solutions of 35 cc. of vinegar diluted with a like amount of water.
The yield from the solution in which the bones had been soaked that had
originally been cooked in the more concentrated vinegar (35 cc. vinegar
and 180 cc. water) gave 0.159 gram of calciii, while the solution from
the bones that had been cooked in the less concentrated solUt1Oi
This study offers no
vinegar and 395 cc. water) gave only 0.113 gram.
data on the effect of a shorter soaking period.
The results of
Moance et al (91) indicate that possibly a short period of soaking in
water before cooking might result in a maximum yield.
The long soaking
of Saner Brauten (page 2) in whole or dilute vinegar is an illustration
that a long time procedure has actually been used.
The fact that the
tough cuts of meat are usually associated with the bony parts ci' the an-
imal night give such a method a twofold purpose:
to break down the con-
nective tissue of the meat and to increase the caloin yield.
lI
OCiTLIJSICS
1. Caleirt was obtained frn the bones in pork spareribs and 'cool'
short ribs when these cuts of meat were cooked with liquid.
2. !merican cider vinegar seemed to be as effective in dissolving calcii.mt
frn the bones as Chinese rice vinegar of the sene total titratable
acidity. iTo correlation was observed between the acidity or the pH
of the cooking solution and the calchi yield.
The calciwn in the scan-
pies prepared with soybean sauce alone or in ebination with vinegar
:as higher than in the somples prepered with vinegar alone.
less effective than vinegar.
The liquid inredients of the cooking solu-
tions seemed to have a ninor effect on the total calci
3. The calci
Tater was
of the scmples.
of the costal cartilage was aTwarently the most
variable factor in the sempling.
The costal oartilagt of pork
which seemed to increase with the age of the animal, contained an
atraciable emouw:
icii in the older pigs.
4. analyses of snples from fcureen pigs, ranging in age from four
to nine months, suggested that the oa1ci
in cuts of meat con-
taining bone and cartilage increases with the age of the pig.
5. Further investigation might well be carried on to detoiine:
a. the effect of the various methods of cooking with liquid on the
calci
of' the bone; b. the yield of caloitta from other bony cuts of
meat with and. witho
cartilage; c. the offect of soaking before and
after cooking: d. the utilization in balances on hisaan beings of the
ea1ci
obtained from such cubs of neat.
EPJ
Sri Tjj
1.
esults zith pork paroribs repared by any one of the
recioes used in this entire study indicate that the roduet
i ctrenely variable in oaiciini contmS.
.
Y:esults indicate that the ac of the pi has nore effect on the
total calcilxii obtained fron the bone and cartilage than the coo].:-
ir inrodieiits, the total acidity, or the pIT of the solution.
The oarti?go, nhrtob apoareiitly increases in calci
content
with age, nay furnish an appreciable atount of this element in
the edible portion.
:6
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