milking time.
 A fatty phase composed of cells, fat (2 to 5 m of
diameter) which contain lipids and fat-soluble elements,
the fatty globules are surrounded by phospholipids and
protein membrane.
 A colloid phase comprising casein micelles
associated with phosphates and citrates of calcium and
magnesium (Michel, 2005).
 An aqueous phase consisting of the soluble
proteins (whey protein), lactose and minerals
(electrolytes). There is an inverse relationship between the
content of lactose and minerals, in order to keep the milk in
relation with the isotonic blood plasma.