hydrolysis of beta-galactosides using polymer-entrapped lactase: A study towards producing lactose-free milk.

TLDR: In this paper, a yeast lactase, Maxilact, was immobilized in crosslinked polyacrylamide using a bead-polymerization technique, and the polymer beads obtained, containing the entrapped enzyme, were used for the preparation of lactose-free milk.

Abstract: A yeast lactase, Maxilact, was immobilized in crosslinked polyacrylamide using a bead-polymerization technique. The polymer beads obtained, containing the entrapped enzyme, were used for the preparation of lactose-free milk. The binding yield of the enzyme and residual enzymic activity in the “enzyme beads” were studied as a function of the amounts of monomeric acrylamide and cysteine and bovine serum albumin present as protecting agents in the monomer-enzyme solution prior to polymerization. A maximum of about 75% of the enzyme could be immobilized using a 20% (w/v) solution of acrylamide plus N, N′-methylenebis-acrylamide, whereas the highest activity quotient (bound to free) of about 60% was observed on using a 25% solution. The presence of cysteine increased the activity by up to 30% and that of serum albumin up to about 15%.