To study the quantity of Casein in different samples of milk.Mr.for the help .ACKNOWLEDGEMENT I would like to express my immense gratitude to our chemistry teacher.N.LAL.K. Requirement .Iwould like to thank all others who have rendered their hearted Support in the succesful completion of this project. Lastly. Introduction 2.and guidance he provided for completing the investigatory project. Aim 3. Most of all i thank our principal sir. INDEX 1.For providing us the facilities and opportunity to do this project.I also thank my parents who gave there ideas and inputs in making this Project along with the person who provided the fresh milk of different animals. Procedure 6.Carbohydrates. Conclusions 8. Theory 5. Vitamins Proteins. .4. Observations 7. References Introduction Milk is a complete diet as it contains in its Minerals. 9 4.7 3.3 3. Casein has isoelectric pH of about 4.Fats And Water. Average composition of milk from different sources is given below: Source of milk Water (%) Carbohydrates (%) Cow Goat 87.2 4.0 Mineral (%) Protein (%) Fats (%) 0.7 0.9 4.1 87. It readily dissolves in dilute acids and alkalies.7 and can be easily separated around this isoelectric pH. These micelles have negative charge and on adding acid to milk the negative charges are neutralized.4 3.8 Caesin is a major protein constituent in milk & is a mixed phosphor-protein.Casein is present in milk as calcium caseinate in the form of micelles. Ca2+-Caesinate +2CH 3COOH(aq)--Caesin+(CH 3COO)2Ca . AIM To study the quantity of Casein in . REQU I REMENTS 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 sulphate solution Theory Natural milk is an opaque white fluid Secreted by the mammary glands of Female .different samples of milk. Fats and Water and is a complete balanced diet .called curd. it forms semi-solid mass. Carbohydrate. PROCEDURE 1. Mineral Vitamins.Fresh milk is sweetish in taste.mammal . followed by putting 20 ml of cow·s milk into it and adding . A clean dry beaker has been taken. These bacteria convert lactose of milk into lactic acid which is sour in taste.The main constituents of natural milk are Protein. However . when it is kept for long time at a temperature of 5 degree it become sour because of bacteria present in air . When the acidity in milk is sufficient and temperature is around 36 degree. In acidic condition casein ofmilk starts separ ating out as a precipitate. 3. OBSERVATIONS Volume of milk taken in each case = 20 ml . 2. The milky solution was heated to about 40 o C and add 1% acetic acid solution drop-wise. The solution was filtered and transferred the pre cipitates in another beaker. Filtered the precipitate.20 ml of saturated ammonium sulphate solution slowly and with stirring. Added about 30 ml of water to the precipitate. washed with water and the precipitate was allowed to dry. Only Caesin dissolves in water forming milky solution leaving fat undissolved. Fat along with Caesin was precipitate out. The experiment was repeated with other samples of milk. 6. 5. Weighed the dry solid mass in a previously weighed watch glass. when casein got precipitated. 4. 5-3.Name of milk Cow milk Goat milk % of casein 2.5-3.com .org www.indiainfo.encyclopedia.3 BIBLIOGRAPHY http://www.6 2. in www.icar.com www.com .caesinepro.sciencejournals.zetascience.com www.www.nic.