Degradation kinetics of bioactive components, antioxidant activity, colour and textural properties of selected vegetables during blanching

摘要

Bioactive components of fruit and vegetables play an important role in scavenging free radicals and protect the body from degenerative diseases. A kinetic study was conducted to quantify the losses occurring in bioactive components, antioxidant activity and changes in colour and firmness of four commonly used vegetables (beetroot, green pea, eggplant and green pepper) during heat treatment (70-90 degrees C). The study revealed that logistic model can predict the variation in bioactive components and antioxidant activity with higher R-2 and lower root mean square error (RMSE) as compared to first order model due to logarithmic reduction in these properties in the beginning of the process itself. However zero and first order kinetic models were found suitable to predict the changes occurring in colour and firmness respectively during blanching. D, z value, activation energy (E-a), activation enthalpy and entropy were calculated for all measured parameters for selected vegetables in the temperature range of 70-90 degrees C. These finding would be useful in designing thermal processes and related calculations for these vegetables.