Thermal inactivation of milk lipoprotein lipase

: The kinetics of thermal inactivation of cow's milk lipoprotein lipase (LPL) was studied. LPL inactivation can be described by the first order q equation. Thermodynamic parameters of LPL inactivation were calculated. In the range of physiological temperatures LPL existed as two conformers. The temperature of conformation conversion was 41.5 degrees C. Glycerol increased thermal stability of milk, whereas water dilution of milk, pH shift to the acid or alkaline zone, and glycine addition to milk decreased it. It is suggested that casein micellae stabilize milk LPL.