Effect of different drying methods on the quality of blueberry

The effects of five drying methods,including hot air drying,vacuum freeze drying,short- and medium-wave infrared radiation drying,hot air and microwave vacuum combined drying and explosion puffing drying on the physical properties and nutrients of blueberry were investigated. The results showed that hot air and microwave vacuum combined drying led to the largest rehydration ratio followed by explosion puffing drying,vacuum freeze drying,hot air drying and short- and medium-wave infrared radiation drying. Hot air drying led to the largest hardness followed by short- and medium-wave infrared radiation drying,explosion puffing drying,hot air and microwave vacuum combined drying and vacuum freeze drying. The change of color was not significant among different drying methods.After these five methods' treatments,all the blueberries showed nutrients lost. Among them,vacuum freeze dried blueberry kept the highest nutrients.