Experiments on osmotic dehydration of carrot at vacuum pressure

In order to obtain the optimum process conditions of carrot vacuum osmotic dehydration, the effects of slice thickness, vacuum degree, solute liquid concentration and temperature on carrot vacuum osmotic dehydration were investigated by experiment. The results indicated that the osmotic dehydration efficiency was improved obviously at vacuum condition. The carrot dehydration and solid gain rate increased with decreasing slice thickness and increasing vacuum degree, concentration and temperature of sucrose solution. The increasing rate of solid gain rate was higher than the dehydration rate obviously when the vacuum degree was decreased to about 10 kPa. The optimized technological parameters of carrot osmotic dehydration at pulsed vacuum pressure were 4mm slice thickness, 30kPa vacuum degree, 60% solute liquid concentration and 40℃ temperature. The weight loss rate reached 40.1% under the above conditions and osmotic dehydration time 240 minute. These research results provided technical basis for carrot drying pretreatment.