Effect of enzymatic lipophilization on the functional properties of bovine αlpha-lactalbumin

Bovine α-lactalbumin (α-LA) was enzymatically modified with a lipase from Rhizopus orizae in an organic environment which catalyzed the covalent bonding of different length chain fatty acids, at reaction times of 3 and 7 days. Structural changes and functional properties of native and enzymatically modified α-LA in a pH range from 3 to 10 were analyzed. The degree of modification was higher than 40 %. The enzymatic lipophilization modified the functionality of the α-LA due to the increase in the surface hydrophobicity. In general, the surface properties were improved by the lipophilization specially at alkaline pH values, increasing the emulsifying activity more than 60 % and showing higher foam stability.

Keywords: lipophilization, lipase, lactalbumin, functional properties, foaming.