Liposomal encapsulation of flavourzyme and its impact on kinetic properties

Acceleration of cheese ripening is interesting for researchers in the field of food technology. The purpose of this study was encapsulation of Flavourzyme in liposome by heating method and evaluation of its kinetic properties before and after encapsulation. The impact of temperature (12-62°C) and pH (7-9) was investigated on enzyme activity by central composite with 13 treatments. Liposome was prepared by modification of heating method and by phosphatidil choline، Flavourzyme and cholestrol in the amount of 4. 500، 0. 675 and 0. 225 (%w/w)، respectively. Enzyme activity was measured base on enzyme reaction with initial material of L-Leucin P nitroanilid. Kinetic studies indicated an increase in both Michaelis–Menten constant and maximum velocity in encapsulated Flavourzyme (P<0. 05). Optimum incubation temperature and pH of encapsulated enzyme did not show any significant difference in compare to free enzyme. Evaluation of the thermal stability (at 35، 45 and 55°C) showed that encapsulated enzyme was stable at 35°C during 6 h. Also a decrease of stability of encapsulated enzyme has been observed at 65 and 75°C in 1 h. The results showed increased stability of encapsulated enzymes in pH 7 and 8 (7 h)، while it was decreased in acidic condition. The results showed that liposomal encapsulation by heating method did not cause any significant difference on kinetic characteristics of enzyme Flavourzyme but comparison of proteolysis in sample and control indicated gradually proteolysis of casein in the case of liposomal enzyme application. So، it can be concluded that preparation of liposome by heating method is a suitable approach for encapsulation of protease for acceleration of cheese ripening.