The membrane also protects the fat from being broken down by the enzymes present in the milk and thereby causing rancid flavour. 16 Fat is not soluable in water. If you look closely, you can see small globules of fat. The membrane protects the fat from enzymes in the milk which break down fat and cause bad taste. 19 Gentle treatment of milk is important to protect fat globules .
Large globules rise faster from the skim milk than small ones.
Rough treatment breaks down the membrane that protects fat. Protein is built up of amino acids. There are about 20 different amino acids of which 8 are essential for adults and 9are essential for children. These essential amino acids must be found in your food every day so that your body could build up and maintain skin, hair and muscles. Milk protein is rich in these amino acids and has, therefore, a very high nutritional value and a high coefficient of utelization compared to proteins from vegitable food, for instance soya.