Goat genetics

Casein (caseinogen) is present in milk bound as a calcium salt (calcium caseinate). Casein (caseinogen) is one of the main proteins in milk, cheese, cottage cheese and other dairy products, along with whey proteins (albumin, etc.). Casein is not found in the blood and is synthesized in the mammary gland from free blood amino acids. Just like any other protein, casein breaks down during heat treatment, but it is significantly more heat resistant. For its coagulation, exposure is required at a temperature of 130 degrees Celsius. Goat milk, like cow's milk, belongs to the group of casein-predominant, while the ratio of casein and whey proteins in both types of milk is similar and is 75:25 and 80:20, respectively. The dominant casein fraction in goat milk, as well as in human milk, is beta-casein, while the casein proteins in cow's milk are mainly represented by alpha-S1-casein. The absence or low content of alpha-S1-casein in goat milk and a relatively high content of albumin, in contrast to cow's milk, contributes to the formation of a softer, smaller curd size and small loose flakes, which facilitates the digestion of milk by proteolytic enzymes, in connection with which goat milk easier to digest without causing indigestion. Alpha S1 casein in goats is characterized by extensive polymorphism, which is under the control of at least 17 alleles: A, B1, B2, B3, B4, C, D, E, F, G, H, I, L, M, N, 01 , 02. They correspond to different levels of alpha S1-casein in milk (from 0 to 7.2 g / l): A, B1, B2, B3, B4, C, H, L, M - high levels of alpha S1-casein - 3.5 g / l. E - 1.6 g / l I - 1.1 g / l D, F - 0.6 g / l 01, 02, and N - absence of alpha S1-casein in milk