真空微波干燥对黄秋葵品质的影响

The Effect of Vacuum Microwave Drying on Quality of Okra

是研究真空微波干燥对黄秋葵品质的影响,通过在不同干燥时间、真空度和微波功率下进行真空微波干燥黄秋葵试验,得到色差、断裂性、复水率和维生素C含量的变化曲线。结果表明,干燥时间和微波功率增加时,黄秋葵干制品与鲜果相比色差变大,而真空度增大时色差减小;干燥时间在14 min和16 min的较高水平时,干制品断裂性较小,脆性较好,增大真空度也使断裂性减小;收缩率和复水率随时间和微波功率增大而变大,但时间超过14 min时复水率有所下降,增大真空度时,复水率初期增大明显,后期增大缓慢;干燥时间和功率越大,维生素C损失越多,真空度越大,维生素C保留越多。

The purpose is to investigate the impact of vacuum microwave drying on the quality of okra. The curves of color, fracture property, shrinkage ratio, rehydration ratio and the content of vitamin C were obtained by drying at different time, vacuum degree and microwave power. The results showed that an increase in drying time and microwave power resulted in a serious color change when compare the dry products to fresh one. However, the higher the vacuum degree, the slighter the color would change. The fracture property decreased and the brittleness was good as the drying time increased to high level of 14 rain and 16 rain, increasing the vacuum degree also could make fracture property decrease. Shrinkage ratio and rehydration ratio increased with drying time and microwave power increased, but rehydration ratio decreased when the drying time exceeds 14 min, the rehydration ratio of okra were also affected by the vacuum, which made the rehydration ratio increased significantly at the beginning of drying and then slowly. The greater the drying time and microwave power, the more the loss of vitamin C, however higher vacuum are beneficial to save the vitamin C.