Stabilization of β-Galactosidase Encapsulated in Pectin-Alginate Hydrogel and Hydrolysis of Whey Lactose and Whole Milk

The operational conditions of β-galactosidase encapsulated in pectin-alginate hydrogel were investigated as well as its catalytic activity in the hydrolysis of lactose from whey and whole milk. β-Galactosidase encapsulated in pectin-alginate hydrogel showed the best results to yields and diffusional effect and pH range. Thermostability showed considerable income gain for half-life (1.7-fold), activation energy of denaturation (31.6-fold), activation of denaturation (217.3-fold at 40 ºC; 266.8-fold at 50 ºC; 345.6-fold at 60 ºC), and entropy of activation of denaturation (-42.0 J mol 1 K^-1). Reusability of encapsulated β-galactosidase was observed in 8-cycles for the milk whey lactose hydrolysis (51.9%) and 7-cycles for whole milk (55.6%), and the lactose hydrolysis was observed in 13% in milk whey and 10.3% in whole milk after 10 cycles. These results revealed an industrial application potential of β-galactosidase encapsulated in pectin-alginate hydrogel for lactose hydrolysis of milk whey and whole milk processes.

Keywords:
enzyme encapsulation; lactase; thermostability; reusability; lactose hydrolysis