Concentration of amino acids of the curds whey on the ceramic membranes

The process of concentrating amino acids of fresh curds whey produced at the dairy farm owned by Anikieva A.V. was studied (Polevskoy town, Sverdlovsk region) using ultrafiltration in a pilot plant including a module with cylindrical ceramic membranes based on anatase titanium dioxide in an amount of 14 pieces, with a selective layer of а-alumina with pore sizes of 0,01 pm, total membrane area 3,34 m2, produced by OOO «NPO «Keramikfilter» (Moscow). Preliminary chemical composition of curds whey before concentrating has been determined. It was found that protein content is less than 1 %, lactose 4,3 %, fat less than 0,5 %, minerals 0,7 %. In the process of ultrafiltration on ceramic membranes, protein was concentrated 9,8 times, with the mass fraction of protein in the solution being 0,18 % and 0,72 % precipitated. The average selectivity of the membranes KUFE-19 (0,01) for whey protein was 97 %. In the process of analyzing the amino acid composition of curds whey proteins, it was found that in the initial solution the concentration of amino acids was 176,67 mg/l, after concentrating it increased to 279 mg/l, which is by 58 % higher. A part of the amino acids precipitated was not analyzed. It was shown that the largest mass fraction in the initial curds whey solution is glutamine (57,01 mg/l) and aspartic (19,26 mg/l) amino acids, lysine (25,16 mg/l), proline (10,02 mg/l), taurine (9,13 mg/l). It was found that the largest mass fraction in the concentrate of whey proteins in the final solution is aspartic (24,19 mg/l) and glutamine (65,34 mg/l) amino acids, the amount of lysine increased significantly (from 25,16 to 71,59 mg/l), cystine (from 0,12 to 2,11 mg/l) and glycine (from 0,73 to 8,99 mg/l). The concentration coefficients of some amino acids on the membranes of KUFE (0.01) were calculated. It was found that the concentration of cystine (Mr = 240,3 kDa) is 18, glycine (Mr = 75,1 kDa) - 12, tyrosine (Mr = 181,2 kDa) - 0,35, and threonine (Mr = 119,1 kDa) - 0,55.

dairy industry, membrane methods, ultrafiltration, ceramic membranes, curds whey, amino acids