Biochemical composition, drying kinetics and chromatic parameters of red pepper as affected by cultivars and drying methods

Abstract Effects of different drying methods (open-sun, shade, greenhouse, microwave (300-600 W), air-convective (60-80 °C) and freeze drying) on drying kinetics, biochemical characteristics, rehydration ratio, color and total phenolic content of two different pepper cultivars (Bozok and Pinar) were investigated in this study. Significant differences were observed in biochemical traits of the cultivars and response of cultivars to different drying methods was also different. The greatest crude protein, β-carotene and lycopene values were recorded for the freeze dryer application. The greatest ascorbic acid values were obtained from freeze dryer and shade drying. Microwave drying process resulted an increment in total phenolic contents of the samples. Except for shade drying, the other methods reduced the oil contents and drying methods significantly influenced fatty acid composition of the samples. The rehydration ratios increased with increasing microwave powers. Chromatic parameters (L*, a*, b*, ΔE) were also influenced by drying temperatures, which contributed to the discoloring of red pepper during the process of drying.