Influences of microwave vacuum puffing conditions on anthocyanin content of raspberry snack

Microwave technology is fit for the processing of berry products, but it may affect nutrition components of berry fruit. To improve the nutritional value of the berry products, the influences of microwave vacuum puffing conditions on the anthocyanin content of raspberry snack were investigated using central composite experiments. Results indicated that vacuum pressure had the most significant effect on the anthocyanins of berry snack, followed by the puffing time, microwave power, and initial moisture content. The interaction between microwave power and puffing time on the anthocyanins was extremely significant. Under microwave power of 2.68 kW and the puffing time of 81.00 s, the anthocyanin content of raspberry snack was retained at high level. The results can provide some technological basis for the berry fruit products processed with high quality.