Effects of Different Drying Methods on Quality and Polyphenol Oxidase Activities of Flammulina filiformis

The fresh fruit body of F. filiformis was treated with hot-air constant temperature drying,hot-air variable temperature drying,natural drying,microwave drying and vacuum freeze drying methods. To study the effects of different drying methods on sensory evaluation,rehydration ration,expansion ration,crushing ration,nutrients and polyphenol oxidase activity of dried Flammulina filiformis. The results show that the effect of vacuum freeze drying was the best,followed by natural drying. The rehydration rate of vacuum freeze-dried dried F. filiformis was 358.75%,the crushing rate was 76.37%,the expansion ration was 84.52%,the crude protein was 12.07 mg/g,the crude polysaccharide was 34.22 mg/g,and the vitamin C content was 17.18 mg/100 g.The natural drying product had the highest polyphenol oxidase activity of 32.9 U/min,which was higher than other drying methods. In conclusion,quality effect of F. filiformis on vacuum freeze drying was the smallest and polyphenol oxidase activity was the lowest. It was an appropriate method for drying F. filiformis.