Study of Two Different Immobilized Acid Proteases for Wine Application

Abstract
This study compares the hydrolytic efficiency in model wine (pH 3.2 tartaric acid buffer with 12% v/v ethanol) of two immobilized enzymes. Food-grade acid proteases (from Aspergillus saitoi and stem bromelain) were covalently immobilized on two solid supports, aminopropyl controlled pore glass beads and Eupergit®C. The effects of pore diameter, immobilization procedure, and protein properties on the activity of biocatalysts were evaluated to determine the feasibility of immobilized proteases in wine. The results expressed in terms of yield of immobilized enzyme, enzyme activity, and kinetic parameters (Vmax and Km) demonstrated that the best performance of both proteases was when immobilized in Eupergit®C.