Impact of different drying methods on the drying time, energy, and quality of green peas

摘要

The effect of seven drying methods (freeze (FD), hot air (HA), infrared (IR), microwave(MW), hot air-infrared(HA-IR),hot air-microwave(HA-MW),and sun drying(SD) methods on the drying time, the physical, qualitative and antioxidant properties,and the extraction of phenolic and flavonoid compounds in green peas was studied.Six mathematical models were also utilized to predict the moisture content of driedgreen peas. The results showed that the shortest and longest drying times were obtainedby the HA-MWand FD methods, respectively. For all drying methods, thePage model had the best ability in predicting the drying curve. The lowest amountof specific energy consumption was achieved by the MW method. The highest colorchanges and the lowest amount of shrinkage occurred in the FD method. The lowestrehydration ratio was 1.23 in the SD method. The highest pH value of 6.08 wasalso obtained in the SD method. The amount of antioxidant capacity changes and thetotal phenol and flavonoid contents varied between 42.47%-88.28%,4.52-14.59mgGAE/gDW, and 244.62-322.44mg QE/gDW for different methods. The FD methodwas found to be the best way to preserve the product properties. It was further suggestedthat the HA-MWmethod can be a promising technology for drying the greenpeas due to the relatively lower energy consumption, shorter drying time, and higherquality.