Effect of heat assisted high pressure treatment on rate of change in pH and gel strength of acidified milk gel in the preparation of soft cheese

The effect of high pressure (200-600 MPa), pressurization time (0-60 min) and heat treatment temperature (15-65oC) on change in pH and storage modulus (G') of the acidified milk gel in the preparation of soft cheese was studied. The value of the pH of the heat assisted high pressure (HAHP) treated samples was observed to vary from 5.48 to 5.31 after 140 s of acidification, whereas it dropped from 6.38 to 5.16 after 240 s of acidification for the control. It was observed that higher pressure and temperature increased the pH values of the milk gel, whereas the values decreased with higher pressurization time. Similarly, the values of G' of the HAHP treated samples ranged between 384 Pa and 322 Pa after 200 s, compared to 361 Pa after 260 s for the control. High pressure increased the G' value of the HAHP samples, whereas the value decreased with high pressurization time and temperature.