Lipolysis of Butter Oil by an Immobilized Kid Goat Pregastric Esterase

A kid goat pregastric esterase immobilized in a continuous flow, hollow-fiber reactor was employed to hydrolyze anhydrous milkfat, producing lipolyzed butter oil. The effects of temperature and pH on the rate of lipolysis were monitored by titration of the effluent stream for total acidity. The overall rate of hydrolysis was fastest at 40 °C and pH 6.0. The reaction rate was modeled by an expression of the general Michaelis-Menten form based on a ping pong bi bi mechanism. Nonlinear regression analyses indicated that the experimental data were consistent with the form of the ping pong bi bi mechanism that assumes that the rate-controlling step is acylation of the enzyme.