Effects of Different Drying Methods on the Nutritional and Bioactive Components of Radix Puerariae Residue

In this study, the major nutritional component, bioactive component and amino acid composition of Radix puerariae residue were monitored after hot air drying and vacuum freeze drying to unravel the effects of different drying methods on the nutritional and bioactive component. The results were as followed:the starch content of Radix puerariae residue in vacuum freeze drying (53.6%) was significantly higher than that in hot air drying (47.0%), but the protein, reducing sugar and ash content were significantly lower than those in hot air drying, no significant difference of the fat, sucrose, total flavonoids, puerarin and polysaccharides content was found between hot air drying and vacuum freeze drying. And the dietary fiber, crude fiber, lignin, total amino acids, essential amino acids, non-essential amino acids contents of Radix puerariae residue in hot air drying were significantly higher than those in vacuum freeze drying. In comprehensive consideration of determination results of various nutritional and bioactive composition of Radix puerariae residue, hot air drying is suitable for processing Radix puerariae residue in order to keep its quality with the cost of production considered.