A COMPARATIVE STUDY OF VITAMIN
C (ASCORBIC ACID) IN ORANGE,
GRAPES, APPLE AND MANGO JUICES
(ARTIFICIAL)
RUKHSANA TAJ
Department of Chemistry, SBK Women`s University, Quetta, Pakistan.
Email Address of Author: rukhsana.taj88@yahoo.com
ABSTRACT
Basis purpose of this thesis is to determine the ascorbic acid content in two different brands of artificial
fruit juices i.e. Nestle and Shezan. A wide variety of fruit juices that contain vitamin C, particularly citrus
fruit juices. My work is focused on `Orange, Grape, Apple and Mango juices’, because of their ease of
availability in market. Vitamin C is essential micronutrients that are required for the normal metabolic
functions of human body. So, for this purpose quatatively analyzed the vitamin C in artificially available
forms of juices by chemical methods i.e. `Iodometric titration` and second by ` Dye reduction titration`.
`Orange juice` contains higher concentration of vitamin C, while `Mango juice` contain less vitamin C
content and become least acidic among the analyzing juice samples. Ascorbic acid determination results
obtained by` Iodometric titration ` were compared with those obtained by `Dye reduction titration’. The
results obtained by two methods were in good agreement.
Key Words: Artificial juices, Ascorbic Acid, Iodometric titration, Dye Reduction titration.
INTRODUCTION
Juice is the liquid that is naturally found
drying, freezing, evaporation
in fruit and vegetable tissue. Juices can
pasteurization. Fruit juices having many
prepare by mechanically squeezing fresh
antioxidants and vitamins which can
fruits or vegetables flesh without using
benefit
of heat, temperature or solvents. Juice
However, fruit juice can also containing
may be prepared in the home by using a
a lots of sugar .Fruit juice can help the
variety of hand or electric juicers. Many
body by supplying it with antioxidants
commercial juices are filtered to remove
which will help to prevent from many
pulp and fiber. Common methods for
types of cancer and can also help the
processing and preservation of fruit
heart
juices
disease. Continual intake of citrus fruits
include canning,
spray
the
by
body
in
preventing
many
and
ways.
cardiovascular
1
and juices makes good health of our
A quick source of energy that promises
gums and teeth. Take high concentrations
good blood. It lowers the risk of forming
of fruit juices make young children
the blood clots. Grape juice has been
obsess and thrive(Insel etal.,2010).Food
found to stop the growth of breast cancer
dye and preservatives like sodium
cells (Anonymous, 2006). Apple juice is
benzoate present in artificial fruit juices
having high mineral content. It is helpful
cause a distraction and hyperactivity
in the treatment of muscle disorder.
particularly in children, between 8 and 9
Vitamin C is added by fortification,
years of age. Juices with a high fructose-
because
to-glucose ratio and containing sorbitol
(Anonymous,2006) and much of them is
can aggravate the intestines, especially
lost
those already sensitive of infection and
Edwards,2005).Research suggests that
irritation.
apple juice increases acetylcholine in the
Artificial
fruit
juices
having
high
its
during
content
is
variable
processing(Parks
and
brain, resulting in the increased memory
concentrations of sweeteners, flavorings
(Warner,2006).
and sugar can cause tooth decay, leading
Mango juice is rich in nutrients such as
to cavities in children. However, too
vitamin B (B1, B2, and andB3), vitamin
much of artificial juices can causes
C, Vitamin A, Iron, potassium and
problems
such
as
obesity,
dental
calcium.
This
juice
is
very
cavities, and the health complications for
benificialduring the following health
example, type 2 diabetes, hypertension,
condition such as cancer, Heart diseases,
hypertriglyceridemia, and heart disease
Constipation, Excessive thirsty condition
(Ashurt,2005).
and Anemia (Calbom, 2000).
Orange juice with the highest amount of
Vitamin C is very important among all
vitamin C and potassium and a good
vitamins. The importance of vitamin C
source of Folate and thiamin. It also
was described in 1747. Vitamin C play a
contains cancer-fighting photochemical
protective role in the body.Reseach
(Rampersand, 2007).
shows that Vitamin C has found to be an
Grape juice high in vitamin C and the
effective antiviral agent (Sauberlich
best juice for healing wound in the
etal., 1997). Ascorbic acid (AA) is a
intestines.
white
solid,
odorless,
having
the
2
chemical formula C6H8O6 (Yilmaz etal.
levels
2008) .Numerous type of food consists
Dr.Jerry,1995-2005).
of vitamin C.Fruits with high vitamin C
This thesis was carried out with aim to
content
determine the ascorbic acid in artificial
include;
strawberries,
oranges,
bananas,
lemons,
peaches
and
of
vitamin
C(Gordon
and
fruit juices (Shezan and Nestle), such as
grapefruit (Jacob etal. 1999).
`Orange, Grape, Apple and Mango
Vitamin C intake has special effects on
juice`. So, due to this purpose, I
most forms of cardiovascular disease,
quatatively determine the ascorbic acid
cancer, eye disease, thyroid disease, liver
content in artificial fruit juices by
disease, and lung disease. The specific
`Iodometric titration` and by `Dye
health
reduction titration ` and then compare
conditions
Alcoholism,
include:
Alzheimer’s
Acne,
disease
their vitamin C content.
Asthma , Depression, and Diabetes
Methodology:
(Levine, 1986).
A sample was collected from domestic
Symptoms of the vitamin C deficiency
market of Quetta city, artificial fruit
causes
juice shop of Brewery road, A-one city
a
disease
called
including bleeding gums
scurvy
-
and skin
and Jinnah road.
discoloration due to ruptured blood
Research
vessels, iron deficiency and poor wound
samples of juices:
healing respiratory infection can also be
Orange, Red grapes, Apple and Mango
symptomatic
(Artificial Juices)
of
vitamin
C
deficiency(Trpstra,2005).
In the U.S., the recommended dietary
allowance (RDA) for vitamin C of 60
mg daily for men and women. People
who smoke need more vitamin C and
intake of vitamin C for smokers is 35
comprises
of
following
METHOD 1
Vitamin
C
is
determined
by
“Iodometric Titration” method. The
first step is to prepare the solutions.
Preparing Solutions:
mg/day higher than for nonsmokers,
i)1% Starch Indicator Solution
because smokers are under increased
Add 0.50 g soluble starch to 50 near-
oxidative from the toxins in cigarette
boiling distilled water. Mix well and
smoke and generally have lower blood
allow cooling before use.
3
v.
ii)Iodine Solution:
Record the final volume of
Dissolve 5.00 g potassium iodide (KI)
iodine solution. The volume that
and 0.268 g potassium iodate (KIO3) in
was required is the starting
200 ml of distilled water. Add 30 ml of 3
volume minus the final volume.
M sulfuric acid. Pour this solution into a
vi.
Repeat the titration at least twice
500 ml graduated cylinder and dilute it
more. The result should agree
to a final volume of 500ml with distilled
with in 0.1 ml.
water. Mix the solution. Transfer the
Titrating Juice Samples:
solution to a 600 ml beaker. Label the
Add 25.00 ml of juice sample to a 125
beaker as iodine solution.
ml Erlenmeyer flask. Titrate until the
iii) Vitamin C Standard Solution:
endpoint
Dissolve 0.250 g vitamin C (ascorbic
solution until get a color that persists
acid) in 100 ml distilled water. Dilute to
longer than 20 seconds.) Repeat the
250 ml with distilled water in a
titration
volumetric flask. Label the flask as your
measurements that agree to within 0.1
vitamin C standard solution.
ml (Helmenstine, 2001).
Standardizing Solutions:
The results are given in table I.
i.
ii.
until
have
(Add
at
iodine
least
three
METHOD 2
standard solution to a 125 ml
Determination of Vitamin C by
Erlenmeyer flask.
Dye Reduction Titration:
Add 10 drops of 1% starch
Method:
Rinse
burette
Vitamin C (ascorbic acid) in fruit
with
a
small
volume of the iodine solution and
then fill it. Record the initial
volume.
iv.
reached.
Add 25.00 ml of vitamin C
solution.
iii.
is
Titrate the solution until the
endpoint is reached. The first
sign of blue color that persists
after 20 seconds of swirling the
samples such as fruit, juices, vegetable
and
other
determined
such
by
products
the
“dye
can
be
reduction
“method. It is a simple and rapid
method, commonly used for samples
containing least amount of interfering
substance (Tee etal., 1998).
Solution Preparation:
solution.
4
1)2, 6-Dichlorophenol Indophenols
the content of the
Dye Solution (0.025%):
appearance
Dissolve 50mg of dye in 150ml of hot
water containing 42mg NaHCO3. Cool
and then dilute with water up to 200ml
water. Store in colored bottle to protect
2) Meta Phosphoric Acid (3%):
Dissolve 15mg of Meta phosphoric acid
in 40ml glacial acetic acid and 200ml
water. Then dilute it to 500ml with
water.
Standard
for
standardization
pink
15
of
till
color,
which
seconds.
dye
the
The
solution
as
follows:
5ml standard ascorbic acid solution
contains 5mg of ascorbic acid, therefore:
from sunlight.
3)
remained
of
flask
Ascorbic
Acid
Solution:
Dissolve 100mg of ascorbic acid in
small volume of Meta phosphoric acid
(3%) and then dilute to 100ml with
phosphoric acid solution. It will contain
1mg ascorbic acid /ml of the solution.
Procedure:
10ml of the dye= 5mg ascorbic acid
1ml of the dye= 5/10 =0.5mg ascorbic
acid.
This shows that 0.5mg ascorbic acid is
sufficient to reduce 10ml of the dye
solution.
b) Titration of Juice Samples:
Take 20ml of juice sample in a conical
flask. Titrate it against the dye solution
till the appearance of the pink color,
which should persists for 15 seconds.
Repeat the titration until have at least
three measurements (Tee etal., 1998).
The results are given in table II.
a) Standardization of the Dye
Solution:
Take 5ml standard ascorbic acid solution
in a conical flask. Add to it 5ml of met
phosphoric acid solution. Place the dye
solution in a burette and titrate against
5
RESULTS:
Table I. DETERMINATION OF VITAMIN C BY IODOMETRIC TITRATION
NO.
VITAMIN “C”(g/liter)
JUICE
SAMPLES
NESTLE
SHEZAN
1
ORANGE
16.2
7.4
2
RED GRAPES
9.26
6.4
3
APPLE
5.6
5.04
4
MANGO
4.8
4.06
TABLE II. DETERMINATION OF VITAMIN C BY DYE REDUCTION
TITRATION
NO.
1
2
JUICE
VITAMIN “C”(mg/100ml)
SAMPLES
NESTLE
SHEZAN
ORANGE
3.3
3.15
3
3.3
RED GRAPES
3
APPLE
2.5
2.5
4
MANGO
2.37
2.15
6
therapeutic properties. It also helps the
body in forming `connective tissues,
bones, teeth and blood vessels’. It plays
a major role as antioxidant that forms
part of the body defense system against
reactive
oxygen
species
and
radicals,
thereby
preventing
free
tissues
damage. It is widely used in the
treatment of certain diseases such as
`scurvy, common cold, wound healing as
well as infertility`. Table summarize the
Graph I. DETERMINATION OF
VITAMIN C BY IODOMETRIC
TITRATION.
results of the determination of ascorbic
acid in tow brands of fruit juices by
`Iodometric
titration
`.According to
which `Orange juice contain maximum
amount of vitamin C that is 16.2g/liter
(Nestle)
and
7.4mg/100ml
(Shezan).While `Grape and Apple juice`
have relatively high concentration of
vitamin C than `Mango juice` but
comparatively less than that of `Orange
juice`. Table II summarizes the results of
value
of
ascorbic
acid
which
is
determined by `Dye reduction method’.
According
Graph II. Determination of vitamin C
by Dye Reduction titration
to
which
vitamin
C
concentration is comparatively highest in
`Orange juice’, followed by `Grape,
DISCUSSION:
Apple and mango juice’.’ Mango juice `
Vitamin C or L-ascorbic acid is one of
has least concentration of vitamin C.
the
soluble
Result in both tables are tabulated in the
vitamins, Due to its antioxidant and
descending order of vitamin C content
most
important
water
7
as obtained by `Iodometric titration` and
and Mango juices`. It is clear that the
by `Dye reduction method`. It is clear
adequate consumption of artificial fruit
from the result s presented in the tables,
juices with highest concentration of
that there was a definite difference
vitamin C will result in the improved
between vitamin C values obtained by
health condition, thereby reducing the
two methods. Higher value of ascorbic
`Cardiovascular diseases, diabetes, eye
acid obtained by two mthods.Higher
diseases and cancer` etc. Determination
value of ascorbic acid obtained by
of ascorbic acid in citrus fruit juices by `
`Iodometric titration` as compared to
Dye titration method ` has advantages
those
over the conventional method in that it is
obtained
by
`Dye
reduction
method`.
faster
and
simpler
,while
the
`
CONCLUSION:
Iodometric titration` is more lengthy
Bio-chemical difference in the vitamin C
procedure and great care has to be given
values were studied in different citrus
to various steps involved in the method.
juices such as `Orange, Grape, Apple
REFERENCES
Anonymous. (2006).Orange juice prevent
recurrence of kodney the
stones.Hitavad, Daily from
Central India 511, Sep 2, 2006.
Ashurt, P.R. (2005).Chemistry and
Technology of soft drinks and
fruit juices. Wiley- Blackwell
2005.
Calbom, C (2000).The juice lady
Guide to juice for health.
Penguin, 2000.
Gordon and Dr.Jerry. (1995-2005) .How
vitamin c works’. Retrieved.
January
8,
2005:2
from
http://www.home.howstuffworks.com/vitam
in-c-htm.
Helmenstine, A.M., (2001).Vitamin c
determination by Iodometric
titration.
http://www.chemistry.about.com/od/demons
tration experiments//ss/vit.C
titration html.
Insel, P., Ross, D., Mc Mahons, K. and
Bernstein, M.(2010). Nutrition
Jones& Bartlett Learning 2010.
Jacob, R.A., Shils, M., Olson, J., Ross, C.
and Balmose.(1999).Vitamin C
in: Modern nutrition in Health
anddiseases.WilliamsandWilkins
.9thedn:467-482.
69(6):1086-1107.
Levine, M., (1986).New concepts in
biology and biochemistry of
ascorbic acid.N.Engl J Med
1986; 341:892-902.
Parks and Edwards.(2005).Boron in the
environment. Retrieved 2008-831.
Rampersand.G.C. (2007).A comparison
of nutrient density scores for
100% fruit Juice. Journal of
food science; 72 (4): 261-266.
Sauberlic, H.E., Parker, L. and Fuchs.J
.
(1997) .a history of vitamin C in
8
health and Diseases. Marcel
Decker Inc: 1-24.
Terpstra, C. (2005) .Vitamin C in orange
Juice. Microsoft Encarta
Encyclopedia standard Ascorbic
acid. Microsoft Work Suite: 1-5.
Tee, E.S., Young, I.S., Ho, K.H., and
Mizura, S.S. (1998).
Determination of vitamin C in
fresh fruits and vegetables
using dye titration and
Microfluorometric Methods.
Pertanika; 11(1):39-44.
Warner, J., (2006). Apple juice may boost
memory. Researched from the
University Of Massachusetts
Lowell.
http://www.webmd.com/brainMassachusetts
Lowell.
http://www.webmd.com/brain
news/20060804/apple-juiceBoost memory.
Yilmaz, S., Sadikoglu, M., Saglikoglu, G.,
Yagmur. S. and Askin, G.(2008).
Determination of ascorbic acid
in tablet dosage forms and some
fruit juices by DPV.
Int. J. Electrochem sci; 3:15341542.
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