UHT-STERILIZED PEANUT BEVERAGES - KINETICS OF PHYSICOCHEMICAL CHANGES DURING STORAGE AND SHELF-LIFE PREDICTION MODELING

摘要

Strawberry-flavored (S04) and chocolate-flavored (C04 and C20) peanut beverages UHT-sterilized (137 degrees C, 4 sec or 20 sec) and aseptically filled in Tetra Briks were stored for 6 mo at 5, 20 and 35 degrees C. Sensory characteristics and kinetics of physicochemical changes were studied. The changes were of zero (pH of S04, and sedimentation and homogenization indices of all beverages) and first (pH of C04 and C20, viscosity and color lightness of all beverages) order. Reaction rate constant and Gibb's free energy increased with temperature. Activation energy followed Arrhenius equation. Deterioration in beverage sensory qualities highly correlated with increase in sedimentation index and decrease in pH and emulsion stability. Shelf-life prediction models were constructed based on sensory and kinetics data. The shelf-life was estimated to be 4-7 mo for beverages stored at 30-35 degrees C.