Effect of different pretreatments and air-temperatures on quality of green chilli powder

Abstract

Studies were undertaken to evaluate the quality of green chilli powder by using different chemical pretreatments and air drying temperatures in tray dryer. Fresh green chillies were given horizontal cuts of 1cm in order to improve the drying rate after blanching. The chillies were pretreated with blanched in hot water at 90 ºC for 3 minutes, solution containing 1% citric acid, 0.3% sodium metabisulphite, 0.3% sodium metabisulphite and 1% citric acid were subjected to tray drying at different temperatures i.e., 50, 60 and 70 °C. The drying time and drying rate were calculated and compared. Proximate analysis was also carried out like total soluble solids, TA, reducing sugars, ascorbic acid and pH. The results showed the Titratable acidity slightly increased with the increase in drying temperature was found to be almost similar at 50, 60 and 70 °C with no significant variation for both control and pretreated samples. Using NaMS at drying air temperature of 60 °C provide more bright green colour as sulphite inhibits the non-enzymatic browning reaction. In order to obtain acceptable colour value and minimum nutrient losses in green chilli powder the pretreatment of NaMS combined with citric acid can be used with drying temperature of 60 °C.