Effect of high pressures on the composition of milk fat triacylglycerols

This study examines the effect of pressurisation on the composition of milk fat triacylglycerols, which determines its crystallization properties and, consequently, the rheological properties of dairy products. The raw material used in this study was anhydrous milk fat from the stall feeding period, obtained from "extra" type butter, purchased from one of the production plants in north-eastern Poland. Treatment pressure (100, 200, 300 and 400 MPa) and a range of process temperatures (10 and 40 degrees C) were the differentiating parameters. The process of pressurisation was conducted in a U 4000/40 type device manufactured by the Unipress Equipment Division. The results showed that parameters of milk fat pressurisation applied in the experiment did not affect the composition of analysed groups of triacylglycerols in the TAG C26 to TAG C54 range. A two-factor analysis of variance revealed stability of the composition of triacylglycerols in milk fat subjected to pressurisation, regardless of the pressure conditions applied: 100, 200, 300 or 400 MPa, and irrespective of the temperature of the process, 10 or 40 degrees C.