Effects of pretreatments and drying methods on nutritional and sensory quality of raisin

Abstract

A study with three drying methods i.e., cabinet tray dryer, solar tunnel dryer and open sun drying methods with four pretreatments such as, ethyl oil and K2CO3, olive oil and K2CO3 and hot water blanching was undertaken to evaluate the effects of pretreatment and drying methods on nutritional quality and sensory attributes of raisins. Moisture content of grapes variety of Thompson seedless was reduced bellow 16 per cent. Raisins pretreated with ethyl oleate oil 1.5 per cent + K2CO3 3 per cent and dried in cabinet tray dryer had least non-enzymatic browning (0.049), highest carbohydrate (79.42 g 100 g-1), minimum titratable acidity (1.80%) and crud fiber (1.11 g 100 g-1) but, highest non-enzymatic browning, lover nutritional value and low sensory scores recorded for sun dried raisins without dipping pretreatment.