Chemical properties of milk

The processability and functionality of milk and milk products are determined by the properties and concentrations of its principal constituents: protein, lipids, lactose and salts.

Milk fat occurs in the form of droplets or globules, surrounded by a membrane and emulsified in milk serum (also called whey). Milk fat is composed of approximately 400 fatty acids.

The fat globules (called cream) separate after prolonged storage or after centrifugation. The fat globules float on the skim milk.

Homogenization of milk so finely divides and emulsifies the fat globules that cream separation does not occur even after prolonged standing. The key attributes of milk flavor are influenced by its emulsion of fat globules in a colloidal protein solution, accompanied by a slight sweet and salty taste from lactose and minerals, primarily calcium.

The majority of milk proteins are synthesized from amino acids. Proteins of various sizes are dispersed in milk serum. They are called micelles and consist mostly of calcium slats of casein molecules.

Furthermore, milk contains lipoprotein particles, also called milk microsomes, which consist of the residues of cell membranes, microvilli, etc., as well as somatic cells, which are mainly leucocytes.

Various proteins, carbohydrate, minerals and other ingredients are solubilized in milk serum.

Milk contains many acidic and basic groups that result in buffering action over a wide pH range. The principal buffer components in milk are soluble phosphate, colloidal calcium phosphate, citrate, bicarbonate and casein.
Chemical properties of milk