Study of the synthesis of milk main ingredients as components of a polydisperse system

Milk can be regarded as a colloidal system (hydrocolloid), consisting of the dispersed medium, and the dispersed phase. Dispersed medium is formed by the lactose at its constant concentration in the solution. Proteins in a wide range of concentrations make a dispersed phase in milk. Milk fat presents in the dispersed medium to form an emulsion. Proceeding from the fact that the synthesis of the milk ingredients occurs in various enzyme systems, the content and relation of elements of a polydisperse system can be regarded as the indicators of activity of these systems. Based on the analysis of a large number of milk samples ( n = 6338) from Holshtine black mottled cows, we found an inverse relationship between the amount of milk and protein and fat yield. Lactose content differed slightly in cows with the different level of milk yield at the different stages of lactation. Particularly, both on winter and summer diets, a positive correlation of the milk yield and the lactose content was found ( r = 0.27, p 0.05) if compared to low-yielding ones, while the fat, protein and lactose output was 360 %, 403 % and 491 % higher, respectively. Close lactose percent was also observed in the cisternal and alveolar portions of milk yield. It is concluded that the constituent components of milk are synthesized independently from each other, and the milk yield is determined by an amount of the synthesized lactose which provides a relatively constant dispersed media, enough to stabilize the dispersed phase.