Effects of different drying methods on physical and chemical properties of carrot power

Carrot power was made by heated-air drying,microwave drying,vacuum drying and vacuum freeze drying method.The physical and chemical properties of carrot power were studied.The results showed that carrot power dried by heated-air drying had high density,pH and content of vitamin C were the lowest,water absorption index and oil absorption ability were better;carrot power dried by microwave drying had the best water absorption,the lowest water solubility,oil absorption ability and content of vitamin C,density was inferior to heated-air drying,pH and total amino acid ware better than heated-air drying;all values of carrot power dried by vacuum drying were better than heated-air drying and microwave drying,and less than vacuum freeze drying method,water solubility and absorption index of carrot power dried by vacuum freeze drying were in the middle of the four drying methods,density was the lowest,oil absorption ability was the best,content of total amino acid and vitamin C ware the highest.