Comparison of pectinase immobilized by encapsulation and entrapment and their effect on papaya juice clarification

Abstract

The present work explores the immobilization of pectinase through two methods: encapsulation in calcium alginate beads and matrix entrapment in agar cubes and evaluates their effectiveness in clarifying papaya juice compared to free pectinase. An immobilization efficiency of 72.59 ± 2.41 % for 2 % sodium alginate and 91.28 ± 3.62 % for 2 % agar were found to be the best. Optimal enzymatic activity for free pectinase was obtained at 40 °C and pH 6.0, and for both immobilized pectinase at 50 °C. The optimal pH was pH 8.0 for calcium alginate bead-encapsulated pectinase and pH 4.0 for agar cube-entrapped pectinase. The kinetic parameters for free pectinase, encapsulated pectinase and entrapped pectinase were K_m of 25.11 mg/mL, 16.29 mg/mL and 16.00 mg/mL and V_max of 4.57 μmol/mL/min, 2.79 μmol/mL/min and 1.92 μmol/mL/min respectively. The encapsulated pectinase and entrapped pectinase were reused for 5 cycles with 50.55 % and 80.03 % residual activity and remained stable for 15 days. In the application for papaya juice clarification tests, agar-entrapped pectinase significantly improved optical density and reduced viscosity, achieving the best results among the tested pectinase preparations.