Kinetics of green asparagus ascorbic acid heated in a high-temperature thermoresistometer

1999

Thermal degradation of green asparagus ascorbic acid in high-temperature short-time conditions was studied by heating in a five-channel computer-controlled thermoresistometer. Ascorbic acid was heated to between 110  °C and 140  °C and the degradation kinetics were analyzed assuming that two different inactivation mechanisms were occurring, one aerobic and the other anaerobic. The two reactions followed first-order kinetics, with E a=12.3(2.0) kcal/mol and k 125  °C=47.0(3.0)×10–3 s–1 for the aerobic oxidation, and E a=6.1(1.4) kcal/mol and k 125  °C=4.1(0.2)×10–3 s–1 for the anaerobic degradation.