Effects of high pressure treatment on the rennet coagulation and cheese-making properties of heated milk

Heat treatment and high pressure (HP) treatment have received considerable research attention as a means for increasing the yield of cheese curd. However, neither is attractive on its own; in the case of heating because it impairs other cheese-making properties of milk, whereas increases in curd yield by HP treatment of milk can be achieved only at economically unattractive long treatment times. However, when milk is heat-treated (10 min at 90 °C) and subsequently HP-treated at a pressure ≥ 250 MPa, an increase in the yield of cheese curd by ∼ 15% can be obtained, while the strength of the renneted milk gel is increased and the rennet coagulation time is reduced. These effects can even be obtained when the pressure is released immediately after the desired level is reached.