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EVALUATION OF COMMERCIAL MILKS AND NON-MILKS
THE EVALUATION, PREPARATION, AND MANIPULATION OF COMMERCIALLY
SOLD MILK AND NON-MILK PRODUCTS
CHAYNA ROBINSON
LAB PARTNER: ERYN ORTIZ
LAB SECTION THURSDAY 5:15-8, TA: ALEXA FARRAR
10/30/2014
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EVALUATION OF COMMERCIAL MILKS AND NON-MILKS
PART I: THE EVALUATION, PREPARATION, AND MANIPULATION OF
COMMERCIALLY SOLD MILK AND NON-MILK PRODUCTS
PART II: PURPOSE OF THE EXPERIMENT
A variety of milks and milk products dominate the commercial food industry for the
purpose of incorporating moisture into recipes for batters and dough, and as an important
ingredient in creamy soups, sauces, puddings and foams. They also serve as flavor contributors
to a wide variety of other commercially made products. Throughout this experiment, a variety of
tests were done to identify characteristics of multiple samples of milk. These tests included
sensory analysis to compare multiple commercial milk products, understanding consistency
differences with different flour to milk ratios, testing the effect of heat and acid on the proteins
casein and whey in fresh, whole milk, the preparation of white sauce and milk foams,
investigating the effect of temperature on whipped cream, preparing butter from whipping cream
and preparing vanilla puddings made with whole milk and non-dairy milk substitute.
PART III: METHODOLOGY
All experiments were conducted in the test kitchen of Grover Center by students enrolled
in Nutr 2200.
To begin, a sensory analysis for various commercial milk products was conducted to
compare the appearance, consistency, flavor, aroma, and composition with one another. Each
student was asked to sample all of the following milk products lined along the center island in
the test kitchen; Almond Breeze Original, Silk Coconut Milk, Silk Original Soy Milk, lactosefree milk, hemp milk, condensed milk, Vitamin D milk, 2%, 1%, skim, cultured buttermilk,
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unsweetened kefir, and goat’s milk and report on the appearance, aroma, flavor and consistency
after sampling, noting any compositional differences read from the labels of the milk containers.
Next, the effect of heat and acid on milk was tested, first of which was the effect of heat
on fresh milk. Using a one quart saucepan, 125 mL of whole milk was placed over low heat on
the stove uncovered, unstirred, and not boiling. The heating process continued until a thick skin
developed on the surface of the milk and precipitate was detected on the bottom of the saucepan.
The students were instructed to pay no attention to the milk while in the heating process
(Brannan, 2013; p 94).
Then the effect of acid on fresh milk was tested, first by measuring out one cup of whole
milk in a two cup glass measuring cup. The pH of the milk was determined using provided pH
strips and the value was recorded. Once recorded, 5 mL of vinegar was added and thoroughly
mixed with the milk. The milk then stood for two minutes and the pH was taken again. Along
with testing the pH, additional observations relating to the thickness of the milk and any curd
formations were asked to be taken in account. This process, of adding 5 mL of vinegar, letting
the milk sit, and retesting for pH, was repeated six times until a total of 35 mL of vinegar had
been used in 5 mL increments.
In the next experiment, basic white sauces or béchamel sauces were prepared. To prepare
the basic recipe, these basic ingredients were gathered; 2 tablespoons all-purpose flour, 2
tablespoons butter or margarine, ½ teaspoon salt and 1 cup whole milk. To begin preparing this
recipe, the butter was melted in a one-quart saucepan over low heat, and once melted, the flour
and salt were added and blended in order to form a roux. The roux was cooked for 3-5 minutes
until bubbly. The milk was then stirred in, blended well in order to prevent any clumps. Over
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medium heat, the mixture continued to cook as it was stirred continuously. Once the sauce was
noticeably thicker, it was cooked for two additional minutes. After cooking, the mixture was
cooled to 120 degrees F and the viscosity was determined using a Brookfield Viscometer as well
as a line spread test. Temperatures were recorded for both.
Along with the basic béchamel, three other variations were prepared. The first of the
three was the same as the basic recipe except one tablespoon of all-purpose flour was used. The
second was the same as the basic recipe except three tablespoons of all-purpose flour were used.
And lastly, the final variation was the same as the basic recipe except one cup of skim milk was
used in place of the original whole milk. The line spread test and Brookfield Viscometer were
used to test the viscosity of all three additional variations.
To compare vanilla puddings using different types of milk, four variations were prepared.
The first was the original, and the base for all of the other variations. The ingredients for the
basic recipe included 1/3 cup granulated sugar, 3 tablespoons cornstarch, 1/8 teaspoon salt, 2
cups milk, 1 tablespoon butter, and 1 teaspoon vanilla extract. A two-quart saucepan was
obtained and the sugar, cornstarch, and salt were combined. Then the milk was gradually
incorporated and constantly whisked to prevent clumping. Over medium heat, the mixture was
constantly stirred and brought to a boil. Once boiling, it was cooked for one minute, making
certain that it was not over-cooked. After the one minute of cooking, the saucepan was removed
from the heat and the butter and vanilla were added in. The pudding was then taken off the heat,
poured into a glass container, covered with plastic wrap, and then placed in the refrigerator to
chill.
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EVALUATION OF COMMERCIAL MILKS AND NON-MILKS
The same process was repeated three more times using three different variations, in
addition to the basic version. The first variation was the same as the basic recipe except
reconstituted dry milk was used instead of the whole milk. The second variation was the same
except soy milk was used instead of whole milk and the last variation used one cup of whole
milk instead of the original two cups, and then when the pudding was finished and of a very
thick consistency, 8 ounces of yogurt was stirred in. All variations were then sampled and the
appearance, flavor, and texture of each variation were recorded.
Lastly, to compare the preparation, stability, and characteristics of various milk foams,
five variations were prepared. The basic preparation is as follows; beat 125 mL of cream or milk
with electric mixer at high speed until the whipped cream began to thicken. Once noticeably
thicker, the speed was lowered and the beating continued until soft peaks began to form, making
sure not to overbeat. Whipping time, or the time it took to produce foam, was then recorded.
Next, the whipped foam was placed in a coffee filter lined, large funnel situated in a 100 mL
graduated cylinder. The height of the foam within the funnel was measured by probing with a
ruler and once more after 30 minutes. The volume of the liquid that accumulated over the 30
minutes was also measured and recorded.
Variation 1 used a cold bowl and cream. To begin, both a medium bowl and the beaters
were chilled. 125 mL of refrigerator-temperature whipping cream was placed into the chilled
bowl and the same procedures from the basic preparation followed.
Variation 2 used a warm bowl and cream. The same instructions for the basic preparation
were followed except the bowl, beaters and cream were all at room temperature.
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Variation 3 used evaporated milk. Again, the steps for the basic preparation were
followed except 125 mL of undiluted evaporated milk was used. 5 mL of lemon juice was then
added to the evaporated milk at the beginning of the whipping process. The mixture was beat to a
stiff foam using a high speed electric mixer.
In variation 4, the steps for the basic preparation were followed except 125 mL of
reconstituted non-fat milk solids were used. 5 mL of lemon juice was then added to the milk
solids at the beginning of the whipping process, and then beaten to a stiff foam using a high
speed electric mixer.
The final variation, variation 5, used buttermilk and did not follow the same procedures
as the basic preparation. 250 mL of whipping cream was beat at room temperature using a high
speed mixer. It was beat until the butter separated from the buttermilk. The time of beating was
recorded, as well as the volume of the buttermilk and the weight of the butter.
The whipping time, height of the foam initially, height of the foam at 30 minutes and the
volume of the drainage at 30 minutes was recorded for each variation.
There were no major changes made to any of the general procedures for all experiments.
PART IV: RESULTS
The results for the first experiment were based primarily on sensory analysis of each
individual. The evaluations of different types of milks are listed in Table 1. Some commonalities
among the samples include a white or an off-white color. Ranging from very watery and very
thin (skim) to very thick and yogurt-like (Kefir), a caramel-like consistency (condensed milk)
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and very thick and curdled (buttermilk), the appearance and consistency of the samples were
very different.
Table 1.
Evaluation of Various Commercial Milk Products
Type of Milk
Appearance
Aroma
Almond Breeze
Cream colored
Almondy, nutty
Original
Flavor
Almond aftertaste
Silk Coconut
Milk
Silk Original
Soymilk
Pure white
Coconut
Sweet, coconut
Pale yellow
Faint aroma
Soy flavor, faint
vanilla taste
Lactose-free
milk
Hemp milk
White, milk-like
Smells rancid
Light brown
Cut grass, earthy
Baby formula,
off tasting
Nutty
Heavy whipping
cream
Condensed milk
Off-white,
chunky, creamy
Golden, caramel
colored, light
brown
Rotten milk
Spoiled
Rotten milk
Caramel-like,
sweet
Vitamin D
Off-white
Milky (most
rich)
2%
Off-white, less
opague than
whole milk
Off-white
Milky
Rich, most
flavorful of
cows’ milks
Less rich than
whole
Skim
Most off-white,
least opague
Cultured
buttermilk
Unsweetened
Kefir
Thick, curdled,
opague
Thick, white
Milky, least
flavorful, most
watery
Rotten yogurt
Goat’s milk
Light orange/tan
1%
Milky
Hardly any
flavor
Watery, hardly
any flavor
Consistency
Not too thick, but
thicker than
cow’s milk
Thin liquid
Thick liquid,
consistency of
baby formula
Thick, milk-like
Like soy milk but
thicker than milk
Thick, chunky
Caramel
consistency,
thick, heavy,
gooey
Thick
Thinner than
whole milk, but
still thick
Thicker than
skim
Thin, watery
Curdled
Thick, creamy
Smells like
yogurt
Yogurt
Sweet, milky
Tastes like hay,
like the goat’s
diet
Very thick,
thickest of all
samples
Somewhat thick
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EVALUATION OF COMMERCIAL MILKS AND NON-MILKS
The results from the second part of the experiment in which the effect of heat was tested
on fresh milk concluded that a ‘skin’ or film of casein lined the surface of the milk, a whey
precipitate formed at the bottom of the saucepan, and lactose was the component that browned at
the bottom of the saucepan. The addition of heat caused the skin on top to thicken.
Next is the effect of acid on whole milk. The more vinegar that was added to the milk, the
lower the pH became. From 5 mL to 20 mL, the pH stayed at a constant 5.5. At 25 mL of vinegar
and 30 mL of vinegar, the pH dropped to 5.0. Finally, at 35 mL, the color on the pH strip read
between 4.5 and 5.0 so it was concluded as 4.7.
The thickness and curd formation both increased as the pH dropped and the amount of
acid (vinegar) increased. Initially, the pH of the milk was 6.5 and the pH of the vinegar was
initially 2.7.
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Table 2.
Relationships Between Acid and pH in Whole Milk
Amount of Vinegar Added
pH
Observations of Mixture
0 (Regular Milk)
6.5
Opaque, pure milk
5 mL
5.5
No effect
10 mL
5.5
15 mL
5.5
20 mL
5.5
25 mL
5.0
30 mL
5.0
35 mL
4.7
Slight curding, very little curd
formation
Same as above, starting to
stick to sides of glass, tiny
curds
Thickening, slight curds,
sticking to edges of glass
Thickening, curds sticking to
spoon and edges of glass
Cream consistency,
thickening, bigger curds,
sticking to spoon/glass, less
opaque when dripping off
spoon
Curds very evident, thick, less
opaque when coming off the
spoon
Plain Vinegar
2.7
n/a
The results from the experiment in which the basic white sauces were made ranged
widely, so the averages were found and displayed in Table 4. Table 3 shows the original results
without averaging.
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EVALUATION OF COMMERCIAL MILKS AND NON-MILKS
Table 3.
Basic White Sauce Variations and Results
Variation
Linespread
Brookfield Viscometer
1 tbsp flour
13.5
78
1 tbsp flour
21.5
7M
3 tbsp flour
20
7300
3 tbsp flour
10
1.75*10^8 cp
Original
6
4
Original
11.25
24
Skim
15
13,600
Skim
10.88
10 M
*Note. The information in Table 3 demonstrates exact data directly given by Nutr 2200 Students
Table 4
Basic White Sauce Variations and Result Averages
Variation
Linespread
Brookfield Viscometer
1 tbsp flour
17.5
3.5 M
3 tbsp flour
15
87.5 M
Original
8.6
14
Skim
25.9
5M
4*Note. The information in Table demonstrates exact data directly given by Nutr 2200 Students
The linespread results show that the original preparation of the white sauce was the
thickest, only scoring an 8.6. Next was the variation with 3 tablespoons of flour (15), 1
tablespoon of flour (17.5) and the thinnest was the variation with skim milk (25.9).
The Brookfield Viscometer results show that the 3 tablespoons of flour variation was the
most penetrable (87.5M) and the original was the least (14). The linespread and the Brookfield
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results for the original and the 1 tablespoon flour variations match up, proving that the original
was the thickest and the 1 tbsp. flour version was the second thickest.
Next was the vanilla pudding experiment with the different types of milk. The basic
recipe was thick and pudding-like in consistency with a taste strong of vanilla extract. The
reconstituted dry milk created a thinner pudding than the original. Soy milk produced a pudding
that was thick and chunky, and the 1 cup whole milk with yogurt variation created an even
thicker, clumpier version of pudding. The flavor remained the same between all of the variations,
with a sweet vanilla flavor. The texture ranged from thin to very, very thick and the colors
remained pretty constant with the exception of the soy milk version which was a bit darker in
color than the others. Table 5 shows the observations recorded for each variation, including the
appearance, flavor, and texture.
Table 5.
Appearance, Flavor and Texture of Pudding Variations
Variation
Appearance
Flavor
Basic
Thick, pudding-like
Vanilla extract
Texture
Creamy, smooth,
pudding consistency
Reconstituted dry
Thin, cream colored
Strong vanilla flavor
Watery, soupy
Darkest of the four,
Sweet
Thick, chunky
Vanilla, sweet
Very, very thick,
milk
Soy milk
chunky, goopy,
pudding clumps
1 cup whole milk with
Pasty, very thick,
yogurt
clumpy
gelatin-like texture
Last are the results for the whipping times, heights and drainage volumes for the milk
foam experiment (Table 6) and their averages. Since multiple pairs of students performed each
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treatment, both data sets are included, except for the NFDM and the buttermilk which only had
one set of data. The buttermilk data is displayed in Table 7.
From the shortest whipping time to the longest whipping time, the order is as follows:
NFDM with a one minute whipping time, the cold bowl variation with an average of 2.35
minutes, warm bowl (3.2 minutes) and the evaporated milk at a ten minute whipping time. The
average heights of the foams at 0 minutes were pretty similar among the variations with 5.5 cm
(cold bowl), 4.5 cm (warm bowl), 6.6 cm (evaporated milk) and 9 cm for NFDM.
Despite having the highest initial foam height, NFDM had the lowest average foam
height after 30 minutes at 0 cm. The others remained pretty similar; cold bowl at 4.75 cm, warm
bowl at 4.5 cm, and evaporated milk at 4.25 cm (on average).
Table 6.
Different Treatments of Milk Foams and the Effects on Whipping Time, Height, and Drainage
Treatment
Whipping Time
Height at 0 min Height at 30 min
Drainage at 30
(Data Set 1, Data (Data Set 1, Data (Data Set 1, Data
Min
Set 2, Average)
Set 2, Average)
Set 2, Average) (Data Set 1, Data
Set 2, Average)
Cold bowl
2.2 min, 2.5 min,
4 cm, 7 cm,
3.5 cm, 6 cm,
None, 1 mL,
Warm bowl
Evaporated milk
NFDM
2.35 min
5.5 cm
4.75 cm
0.5 mL
2 min, 5 min,
5.8 cm, 3.2 cm
5.4 cm, 3.6 cm.
None, None,
3.2 min
4.5 cm
4.5 cm
n/a
12 min, 8 min
8.75 cm, 4.5 cm,
8 cm, 0.5 cm,
53 mL, 93 mL,
10 min
6.6 cm
4.25 cm
73 mL
1 min
9 cm
0 cm
105 mL
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The last treatment was that of the buttermilk in which a butter was produced. The
whipping time was 3 minutes, the weight of the butter produced was 91 grams and the volume of
the remaining buttermilk was 75 mL.
PART V: DISCUSSION
These tests were done to analyze the many properties of commercially sold milk and milk
products, as well as to prove that heat and acid have very different effects on milk. While
evaluating the milk products, it was common for the products that were not cow’s milk to be
thicker in consistency and more off-white in color than regular whole, 2%, 1% and skim milk.
Skim milk was the most watery of the cow’s milks and was reported to have the least amount of
flavor, which can most likely be contributed to its very small fat percentage at 0.2% milk fat.
The thickness of the non-dairy products can be explained by the ingredients listed on the
nutrition labels. The naturally occurring carbohydrates in dairy milk, such as lactose and its
monosaccharide components (glucose and galactose), are replaced by gums and starches that
enhance the cohesiveness and fluidity of the non-milk ‘milks’ (Feder, 2014).
At 9 g of total fat per serving, the lactose-free milk had the highest fat content of all the
samples tasted. It was reported that the lactose-free milk was thick, and ‘off’-tasting; rancid even.
This seemed interesting because it contains no lactose. Typically in milk, lactose breaks down
and produces lactic acid, which in turn makes the milk ‘spoiled’ by producing the casein proteins
that eventually form the curd. Since the lactose-free milk did not contain lactose, and contained
the most fat, I would assume that it was take the longest time to spoil but this was not the result.
Since the milks were not cooled to slightly above freezing point, microorganisms picked
up from the environment may have quickly soured and cooled the milk. The milk was at room
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temperature for the duration of the lab which may have increased the multiplication of spoilage
bacteria, inducing chemical changes in the milk (Encyclopedia Britannica, 2014).
The effect of heat on whole milk yielded results that were similar to what was expected.
The skin at the top of the pan upon heating was the casein proteins separating out from the rest of
the milk because casein is affected little by heat. The evaporation of water from the heated milk
in an open saucepan resulted in a concentration of casein, milk fat, and calcium and phosphate
salts at the surface (Brannan, 2013; p 93); this is the ‘skin’ as shown in Figure 1.
The precipitate at the bottom of the saucepan, shown in Figure 2, was a precipitate
formed by denatured proteins. Whey is affected greatly by heat, which is why it accumulated on
the bottom of the saucepan. When exposed to heat, the water in the shells of these proteins is
removed which is normally what keeps them stabilized (Brannan, 2013; p 93). When they lose
their stability, they precipitate to the bottom and may even scorch. The browning on the bottom
of the pan can be attributed to the sugar in the milk; lactose. Browning occurs when the sugars
become caramelized, which can also be observed in Figure 2.
Figure 1.
Casein Skin
Figure 2.
Whey Precipitate and Caramelized Lactose
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Whey was affected greatly by heat, but was affected very little by acid. The protein in
milk that was affected by the addition of acid was casein. When an acid interacts with casein
proteins, the micelles break open and attract to one another, resulting in the formation of curds.
In the experiment, very slight curds were formed around a pH of 10 mL. At 5 mL of acid, there
was no noticeable effect on the milk. Upon the addition of 10 mL of vinegar, the milk began to
get noticeably thicker and clumpier. By the time 35 mL of vinegar was added, the pH of the
solution had dropped from an almost neutral 6.5 (regular milk) to an acidic 4.7 and the curds
were very evident. The pH of the milk with a large addition of acid resulted in a pH that was
nearly in between of the milk by itself and the acid by itself.
Hypothetically, fresh milk has a pH of 6.6 to 6.7 on its own. At a pH of approximately
5.2, denaturation of protein begins to occur and at pH of around 4.6 (the isoelectric point of
casein) there is maximum denaturation, resulting in the formation of a gel like substance with
curds (Oregon State U., 2014). This data lines up closely to the data found in the experiment.
The different treatments of milk foams and the various results for whipping time, foam
height and drainage volume are indicative each milk’s foaming properties. The evaporated milk
took the longest to whip into foam, (10 minutes on average) and the NFDM, non-fat dry milk,
took the least amount of time (one minute). The lipid content in each of these milks has a large
influence of their foaming properties. For example, the non-fat milk would produce very stable
foams relatively quickly, whereas the evaporated milk with 19 g of fat per serving took
considerably longer. The milk fat, if present in higher amounts will negatively affect the stability
of the foam (Oetjen, 2014).
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The stability of the foam is influenced by the interactions between the milk proteins and
the air. By whipping the milk, air is introduced, leading to an unstable interface between air and
water, which in turn needs to be stabilized by the absorption of ‘surface-active’ components (the
proteins) that attach themselves to the air bubbles, resulting in a stable foam (Huppert, 2014).
The addition or presence of lipid would disrupt this interaction, so smaller amount of fat is ideal
for preparing milk foams.
The cold bowl and the warn bowl had very little differences when it came to the
whipping time as well as the height and drainage data. From this, it can be concluded that
temperature has little to no effect on milk foams.
The differences in data among the groups performing the experiment for the same milk
could be due to the differences in bowl size, differences in precisely measuring the milk before
whipping, and possible differences in determining when the foams were ‘stiff’ and hit their peaks.
Next was the pudding variations and the different consistencies produced. The
basic recipe, with the full amount of whole milk produced the most desirable pudding, thick and
pudding-like. The soy milk and the whole milk with yogurt variations created puddings that were
even thicker and ‘goopy’ in comparison to the original. As explained in the sensory analysis
portion, the non-dairy milk products were thicker than milk to begin with, so this could be an
explanation as to why the soy milk variation resulted in a very thick consistency. Since the
yogurt was also very thick to begin with, it would be safe to conclude that this is also why the
result was very paste-like and gummy. The dry milk produced a pudding that was very thin in
consistency, with a watery and soupy texture. The fact that the dry milk was a powder, and was
initially mixed with water; the milk that was produced was also relatively thin. If more powder
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were added to the same amount of water, the reconstituted dry milk would have been a thicker
liquid which in turn may have produced a thicker pudding.
Last to discuss is the preparation of basic white sauce using four variations; the basic
preparation, using half the amount of flour (1 tbsp.), using an additional tablespoon of flour (3
tbsp.) and using a cup of skim milk instead of a cup of the original whole milk. The skim milk
recipe and the recipe with less flour than the original yielded results that were similar to what
was expected; they both should have been thinner than the original.
In theory, the flour should have acted as a thickening agent, and the recipe with more
flour should have been thicker than the original. The data shows that the recipe with an
additional tablespoon of flour was almost two times as thin as the original. Some possible
explanations as to why the results were different than expected can be due to some experimental
errors such as not appropriately measuring the flour. Some of the groups of students could have
measured the flour by sifting and some could have measured it by packing it into a tablespoon
measure. These two methods could result in two very different amounts of flour, weight wise.
Another error could have been not allowing the sauces to cool to 120 degrees F before testing the
viscosity. If the temperatures were not consistent among all of the sauces, it is difficult to
compare accurate data between them.
The data concluded from the Brookfield Viscometer also shows experimental error
because the numbers were very inconsistent with one another. The results should not have been
in the two-digit range such as what is listed in the data table for the original version. If all
students used the same spindle number and read the dial correctly, the viscometer readings
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should have aligned with the data from the linespread tests in the same general trend, but this
was not the case.
VII: SUMMARY AND CONCLUSIONS
All in all, there is a wide variety of milk and non-milk products that dominate the market.
These milks behave in different ways when substituted for each other in basic recipes. Whole
milk creates an ideal texture for most sauces and puddings which is creamy and smooth. Nonmilk products used as substitutions for milk in the preparation of sauces and puddings creates a
final product that is thick and clumpy in texture.
Heat and acid have very different effects on the different proteins in milk; heat forms a
whey precipitate on the bottom of a heated saucepan and a film of casein on top. The addition of
acid causes casein to curd and has little effect on whey. The more acid that is added to milk, the
more acidic the milk will become. At around the isoelectric point of casein, 4.6, the proteins are
at their most denatured state and the curds are very evident.
The addition of flour to a basic white sauce is primarily used as a thickening agent and
variation with less create a thinner sauce. Replacing whole milk with skim milk in béchamel
sauces also yields a thinner sauce, most likely due to its lack of fat and its initially thinner
consistency.
Milk foams are created by the proteins in the cream interacting with water and air
molecules caused from agitation such as whipping. When lipids are added, the foam becomes
less stable and takes considerably longer to whip into foam. Buttermilk does not create foam due
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to its high fat content, but instead produces a butter in which the fat globules clump together and
the air escapes, leaving a mass of butter instead of foam (Lower, 2014).
In conclusion, a variety of non-milk products now dominate the shelves of the grocery
store, but regular whole milks and creams have been proven to yield the most desirable end
products for recipes typically made. Non-dairy products are flavorful and offer a wide range of
tastes, from coconut to almond, and are thicker in texture which makes them less desirable in
puddings and other recipes when a texture that is not too thick is wanted.
Milk can be manipulated in many ways, such as being thickened by flour, whipped into a
foam or butter, curdled by acid and burnt by heat which makes it an ideal ingredient for a wide
variety of the foods that we eat.
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References
Brannan, R.G. 2013. Laboratory Manual for NUTR 2200. 93-99
Feder, D. (2014). Dairy Deceptions. Prepared Foods, 183(5), 77-85. Retrieved November 13,
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8-e4fb-4d38-81d6-fdc9503e53a8@sessionmgr113&vid=2&hid=113
Huppert, T. (2014, September 15). Milk Foam: Creating Texture and Stability. Retrieved
November 13, 2014, from http://www.scaa.org/chronicle/2014/09/15/milk-foam-creatingtexture-and-stability/
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