Determining the influence of raw milk β-casein polymorphism on the efficiency of making soft cheese

Abstract

One of the ways to increase the profitability of the cheese industry is the genetic selection of dairy cows to obtain milk with excellent cheese-capacity characteristics. The object of this study is the technology of fresh soft cheeses made by the acid-rennet and thermo-acid method from the milk of cows with different β-casein genotypes (A1A1, A1A2, A2A2). The subjects of research are the physicochemical indicators of raw milk from cows with different genotypes for β-casein (A1A1, A1A2, A2A2); as well as the yield of soft cheeses. The study has established that the physicochemical parameters of milk from cows with different β-casein genotypes are typical for fresh cow's milk. The study showed that with the acid-rennet method, the composition of cheeses from A1A1 milk was 51.60 %, 21.63 %, and 23.62 % of moisture, protein, and fat, respectively. A1A2 milk cheeses contained 50.70 % moisture, 20.96 % protein, and 25.12 % fat. A2A2 milk cheeses consisted of 52.50 % moisture, 20.70 % protein, and 23.71 % fat. With the thermo-acid method, cheeses from A1A1 milk were characterized by the moisture content of 55.13 %, proteins – 23.31 %, and fat – 20.21 %. A1A2 milk cheeses contained 58.13 %, 22.62 %, and 17.98 % of moisture, protein, and fat, respectively. A2A2 milk cheeses consisted of 54.03 % moisture, 22.33 % protein, and 22.25 % fat. The calculation of the production efficiency of soft cheeses from the milk of cows with different genotypes according to β-casein with the acid-rennet method of production is 119.3 % on average, which is more compared to milk A1A2 (by 4 %) and A2A2 (by 7 %). With the thermo-acidic method, the efficiency of cheese production from A2A2 milk is 107.5 %, which is higher compared to A1A2 milk (by 9 %) and A1A1 (by 5 %). The conclusions show that changes in the β-casein genotype in raw milk can affect the yield and quality of cheese, and therefore, the profitability of production