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drying, ascorbic acid, isot, degradation kinetics, mathematical modeling


This study investigated drying and vitamin C degradation kinetics in isot (red peppers) at different temperatures (55, 65 and 75°C) and conditions (vacuum and hot air drying). The drying temperature and method had a significant effect on the loss of vitamin C. Vacuum dried samples at 55°C retained the highest quantity of vitamin C, while the samples dried at 75°C in a cabinet dryer lost the highest amount of vitamin C. The results showed that vitamin C is especially sensitive to the presence of oxygen and higher temperatures. The Weibull model was found to provide the mathematical equation best describing the ascorbic acid degradation kinetics in red peppers, while the Page model best reflected the drying kinetics.

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