Chemistry Class 12th Investigatory Project

7/25/2019 Chemistry Class 12th Investigatory Project

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Submitted by:

Dheeraj Singh

Class:XIthA

Roll No.:18

Under the Guidence of:

Mr.Sudhir MaingiPGT(Chemistry)

Department of Chemistry

Kendriya Vidyalaya No. 1, Pathankot

Punjab


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This is to certify that RAHUL KUSHWAHA, a student

of class XII-A has successfully completed the project

entitled

uantity of casein in milk

under theguidance of Mr. Sudhir Maingi during the year 2015-

16.The project is found worthy of acceptance as final

project for the subject Chemistry of class 12th. He has

prepared the project under my guidance.

Signature of external examiner)

Mr. Sudhir Maingi)

PGT (Chem)(Department of Chemistry)


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Every organized report requires a lot of hard work and seeks a lot of

helpinghands.Uptothecompletionofthisprojectreport,Iwasnotsofar

from this strategy or rule. Apart from the efforts of an individual, the

success of any project depends largely on the encouragement andguidelinesofmanyothers.Itakethisopportunitytoexpressmygratitude

tothepeoplewhohavebeeninstrumentalinthesuccessfulcompletionof

thisproject.

Firstofall,Iwouldliketoshowmygreatestappreciationtoourrespected

teacherMr.SudhirMaingiforhisproperguidanceandmoderationduring

my class. I feel motivated and encouraged every time I attend their

lectures.Withouttheirencouragementandguidance,thisprojectwould

nothavematerialized.ThenIwouldliketogivethankstoourrespected

principal Mr. J.D Guru. I would like to thank him for his tremendous

supportandhelp.

Plus,Iwouldalsoliketothanktomydearfriendsandmydearparentsfor

theircontinuoussupportandhelponthecompletionofmyprojectwork.

Theguidanceandsupportreceivedfromallthememberswhocontributed

andwhoarecontributingtothisproject,wasvitalforthesuccessofthe

project.

Atlast,Iwouldliketorememberandthankeveryindividualwhohelped

me to complete my project report successfully.


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INDEX1. AIM OF PROJECT

2. INTRODUCTION

3. THEORY

4. APPARATUS REQUIRED5. PROCEDURE FOLLOWED

6. OBSERVATION

7. CONCLUSION8. BIBLIOGRAPHY


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AIM OF THE

EXPERIMENT

To study the quantity of caseinpresent in different samples of milk


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INTRODUCTION:

Milk is a complete diet as it contains in its Minerals, Vitamins,Proteins, Carbohydrates, Fats and Water. AverageComposition of milk from different sources are given below:

Sourceof Milk

Water(%)

Mineral(%)

Protein(%)

Fats(%)

Carbohydrates(%)

Cow 87.1 0.7 3.4 3.9 4.9

Goat 87.0 0.7 3.3 4.2 4.8Sheep 82.6 0.9 5.5 6.5 4.5

Casein is a major protein constituent in milk and is a mixedphosphor-protein. Casein has isoelectric pH of about 4.7 and can beeasily separated around this isoelectric pH. It readily dissolves in diluteacids and alkalis.

Casein is present in milk as calcium caseinate in the form of micelles.These micelles have negative charge and on adding acid to milk thenegative charges are neutralized.


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THEORY:Natural milk is an opaque white fluid Secretedby the mammary glands of Female mammal.The main constituent of natural milk areProtein, Carbohydrate, Minerals, Vitamins, Fats

and Water and is a complete balanced diet.Fresh milk is sweetish in taste. However, when itis kept for long time at a temperature of 5degree it become sour in taste because ofbacteria present in air. These bacteria convert

lactose of milk into lactic acid which is sour intaste.

In acidic condition casein of milk startsseparating out as a precipitate. When the acidity

in milk is sufficient and temperature is around36 degree, it forms semi-solid mass, called curd.


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APPARATUS REQUIRED:

Beakers (250 ml)

Filter-Paper

Glass Rod

Weight box

Filtration Flask

Buchner funnel

Test Tubes

Porcelain Dish

Different samples of Milk 1% acetic acid solution

Ammonium Sulphatesolution


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PROCEDURE:

1.

A Clean dry beaker has been taken, followed byputting 20 ml of cows milk into it and adding 20ml of saturated ammonium sulphate solutionslowly and with stirring. Fat along with Casein wasprecipitated out.

2.The solution was filtered and transferred the

precipitates in another beaker. Added about 30 mlof water to the precipitate. Only Casein dissolves inwater forming milky solution leaving fatundissolved.

3.The milky solution was heated to about 40 degree

Celsius and add 1% of acetic acid solution drop-wise, when Casein got precipitated.4.Filtered the precipitate, washed with water and the

precipitate was allowed to dry.5.Weighed the dry solid mass in a previously weighed

watch glass.6.

The experiment was repeated with other samples ofmilk.


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OBSERVATION:

Volume of the milk taken in each case = 20 ml

Name of milk: Percentage of CaseinCow Milk 2.5-3.6Goat Milk 2.5-3.3

Sheep Milk 4.3-4.6


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Conclusion:

Different samples of milk containsthe different percentage of casein.


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BIBLIOGRAPHY

o

Help From Internet

oI

nformation from Library


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oHelp From Teachers

Documents

Chemistry Class 12th Investigatory Project