Effect of Thin-Layer Drying on the Quality Parameters of Persimmon Slices

Abstract

ABSTRACT Persimmon (Diospyros kaki) is an important, underutilized fruit crop of India. The thin layer drying of persimmon slices would make it a perfect snack that can be used in various recipes. The drying process of persimmon slices was optimized using Box–Behnken design in response surface methodology. Three categorical independent drying variables, such as temperature (50–70°C), air velocity (0.5–1.5 m/s), and sample thickness (4–8 mm), were considered for the study. The response variables include drying time, ascorbic acid content, browning index, and rehydration ratio were investigated. The air temperature and sample thickness showed a significant effect on drying time. Browning index and rehydration ratio were significantly affected by air temperature and air velocity. As per the given experimental design constraints, the optimum solutions obtained were air temperature (58°C), air velocity (1.40 m/s), and slice thickness (4 mm). The predicted responses for the optimized combination of the drying process were drying time (442.55 min), ascorbic acid (8.61 mg/g dry matter), browning index (0.396 absorbance unit), and rehydration ratio (5.47%). Therefore, this study would be beneficial for scaling up industrial drying of persimmon slices for commercial production to ensure smooth processing and achieve a profitable path.