CLASS XII CHEMISTRY PROJECT

1. XII
PROJECT FILE
CASEIN AND ITS PERCENTAGE
BY KRISHNA RAWAT
XII - B

2. Acknowledgement
First of all, I would like to express my heartfelt gratitude
and dedicate this to my teachers and thank them for their
faith in me. I would like to express gratitude towards my
chemistry teacher Ms. Sunita Malhotra and thank them for
their guidance support and encouragement I would like to
extend my thanks for her motivation and help in completion of
this project without them this project would not have seen
the light of day.
…Your sincere student
Krishna Rawat
XII - B

3. TIMELINE
Contents: -
Introduction
Theory
Aim
Aim
Requirements
Procedure
Observation
Conclusions
Other results
on percentage
Further
research

4. ABOUT CASEIN PROTEIN
Casein is a phosphoprotein which
contributes to more than 80% of the
total proteins present in milk.
Casein is the predominant protein
in milk that can be isolated to
make casein protein supplements.
Casein protein forms a gel in our
stomach, significantly slowing the
rate at which it’s digested and
absorbed.
In addition to aiding muscle
growth, casein protein promotes
feelings of fullness and contains
beneficial nutrients like calcium
and bioactive peptides.
Casein protein is a common
allergen and should be avoided if
you have a milk allergy.
Casein also contains less of the
branched-chain amino acid called
leucine, which helps kick-start the
muscle-building process.
It is mainly consumed in
two different forms,
namely, micellar casein
and casein hydrolysate.
The major uses include
food preparation, the
medical industry,
cosmetics, and dietary
supplements.
It provides steady flow of
amino acid in our body.
IN SHORT
Casein Structure
Casein consists of a fairly high number of praline
peptides, which do not interact. There are also no
disulphide bridges. As a result, it has relatively little
secondary structure or tertiary structure. Because of this,
it cannot denature. It is relatively hydrophobic, making it
poorly soluble in water. It is found in milk as a suspension
of particles called casein micelles which show some
resemblance with surfactant-type micelle in a sense that
the hydrophilic parts reside at the surface.

5. AIM:
To study casein quantity in different milk samples.
REQUIREMENTS:
CHEMICALS REQUIRED -
(i) Different samples of milk.
(ii) Saturated ammonium sulphate solution.
(iii) 1% acetic acid solution.
PROCEDURE -
1. Wash the beaker (250 ml) with the distilled water and dry it. 2. Take 20 ml of
buffalo's milk in 250 ml beaker and find its weight.
3. Add 20 ml saturated solution of ammonium sulphate slowly with stirring. Fat and
casein will separate out as precipitate.
4. Filter the above solution and transfer the precipitate in another beaker.
5. Treat the above precipitate with 30 ml distilled water. Casein dissolves forming
milky solution whereas fat remains as such.
6. Warm the above contents of the beaker to 40-45°C on a low flame. Now, add 1%
acetic acid solution drop wise with stirring when casein gets precipitated.
7. Filter the precipitated casein and wash with distilled water and dry it.
8. Find the weight of dry precipitate.
9. Repeat the whole experiment with cow's milk, goat's milk and sheep's milk.

6. OBSERVATION -
RESULT-
Different Samples of milk contains different percentage of casein.
Highest percentage of casein is present in Goat's milk.
PRECAUTIONS-
1. Handle apparatus and chemicals carefully.
2. Add ammonium sulphate solution very slowly.
3. Stir milk while adding chemicals.
4. Do not disturb milk after adding ammonium sulphate solution and wait some time
for fat and casein to precipitate out.
5. Take the amount readings carefully with digital weighing machine only.

7. FURTHER RESEARCH:
MODERATE AND HIGH AMOUNTS OF PROTEIN FROM CASEIN ENHANCE HUMAN
ABSORPTION OF ZINC FROM WHOLE-WHEAT OR WHITE ROLLS -
ABSTRACT-
The enhancement of zinc absorption by protein was investigated using a broad range of
ingested protein in combination with either whole-wheat or white rolls.
MAIN POINTS-
1. Zinc absorption from foods is influenced by the amount of zinc consumed and the
presence of other dietary components including protein and phytic acid. Increased
protein content in meals has been associated with increased zinc retention in both
human and animal studies.
2. In that study, each level of protein was from a different protein source; thus, protein
was not the only variable.
3. Casein was chosen as a protein source to allow comparisons to the study by
Sandstrom, which utilized various combinations of milk, cheese, and casein, in addition
to egg and beef.
4. It was hypothesized that protein, by enhancing zinc solubility in the intestine, would
counteract the inhibiting effects of phytic acid and fiber on zinc absorption resulting in
greater enhancement of zinc absorption when protein was added to whole-wheat
rather than white roils.
RESULTS-
Both the protein content and type of flour significantly affected zinc absorption (Table 1).
There was no detectable interaction between the type of flour and the amount of protein
in the rolls, although the differences between whole-wheat and white flour seemed
somewhat greater at lower protein levels.

8. MY PROFILE
“Project
assigned to me
have taught me
numerous
experimental
lessons which in
turn increased my
deep interest
towards science.
”

9. Bibliography
THANKS FOR SUPPORT

10. END