Study on effect of drying temperature and size of kair (Capparis deciduas) on effective moisture diffusivity

Abstract

Drying or removal of moisture helps to reduce the water activity of food product and then increases the shelf life of the food. In the present study, fresh kair were categorized in two group on the basis of size (6.022mm and 9.275mm) and then pretreated in hot water at 100 °C for 5 minutes in 0.1% MgO and 0.1% NaHCO3 solution. The method of drying used for the study was tray drying at three temperature levels i.e. 45, 50, and 55 oC. The complete drying of kair follows falling rate period only. The total time for drying decreases with increase in temperature of drying air from 45 oC – 55 oC. The effective moisture diffusivity of kair varies from 3.68 x10-8 to 1.21 x10 -7 m2/s and it was also found that diffusivity increases with increase in temperature and it was higher for 9.275 mm samples as compare to 6.022 mm size samples.