Effect of drying temperature on the microbial characteristics of osmo-dehydrated carrot slices

Osmotic dehydration of carrot slices was carried out in sugar solutions at different solution concentrations, temperatures and process duration of 120min. The osmotically pretreated carrot slices were further dehydrated in a cabinet dryer at 65 0C for 4hr and microwave oven at an input power of 20W for 22min. and then analyzed for microbial characteristics. The drying temperature and pretreatment as osmotic dehydration had a significant effect on microbial quality. The microbial quality increased with increase of syrup concentration and temperature. The best quality was observed in osmo-tray dehydrated carrot slices treated with 500B syrup concentration and 40 0C syrup temperature compared to osmo-microwave dehydrated carrot slices. The optimum conditions of various process parameters were 30-500B sugar concentration, 30 0C and 40 0C osmotic solution temperature and process duration of 120 min.