Convective drying of kumquat slices: Comparison of different drying temperatures on drying kinetics, colour, total phenolic content and antioxidant capacity

Abstract

This study was carried out to investigate the influences of different temperatures (50, 60, 70 and 80 °C) on the drying kinetics of kumquat slices. Additionally, quality attributes such as colour, total phenolic (TP) content and antioxidant capacity (ATC) of dried specimens at various temperatures in comparison with the fresh sample was determined. In accordance with the statistical findings of ten different thin layer modeling, Logarithmic at 50 °C and the Midilli et al. at 60, 70 and 80 °C models showed the best fit of the experimental data of the kumquat samples when compared to the other models. All colour parameters were changed and it was found that the samples dried at 50 °C had the closest colour values compared with the fresh sample (P < 0.05). There was a decreasing in other quality attributes of dried samples compared to the untreated sample. Specifically, specimens drying at 70 °C had the high-est TP content and ATC among the samples dried at different temperatures.