Journal of Food Engineering, Vol.95, No.1, 99-105, 2009
Use of Weibull distribution for describing kinetics of antioxidant potential changes in fresh-cut watermelon
Changes in antioxidant capacity, vitamin C, lycopene and total phenolic compound retention of fresh-cut watermelon stored at selected temperatures (5-20 degrees C) for 14 days storage were accurately described by a Weibull distribution function. The temperature dependency of the Weibull kinetic rate constants was studied through an Arrhenius-type relationship. The degradation kinetic constants of Weibull model increased with temperature. Therefore, initial antioxidant potential of fresh-cut watermelon was best maintained at storage temperature of 5 degrees C for 14 days. The activation energies for lycopene, vitamin C, antioxidant capacity and total phenolic compounds were 56.5 kJ mol(-1), 55.9 kJ mol(-1), 34.5 kJ mol(-1) and 26.9 kJ mol(-1), respectively. Thus, a high temperature sensitivity of lycopene, vitamin C and antioxiclant capacity related reactions were observed compared to that of total phenolic compounds. (C) 2009 Elsevier Ltd. All rights reserved.
Keywords:Kinetics;Weibull model;Fresh-cut watermelon;Lycopene;Vitamin C;Total phenolic compounds;Antioxidant capacity