The novelty of this paper was to evaluation the effect of intermittent microwave drying (IMD) on the nutritional quality and drying characteristics of persimmon slices. Persimmon slices were treated with IMD at the microwave power levels of 280, 350, 420, 490, and 560 W, and the drying characteristics, nutritional components, and sensory properties were determined and analyzed. The results showed that the drying process of persimmon slices could be divided into three stages; increasing speed, constant speed, and decreasing speed. Meanwhile, the higher the microwave power, the shorter the drying time and the higher the drying rate. With the increase of microwave power, the contents of soluble sugar, soluble tannin, vitamin C, and ash increased gradually, but had no obvious effect on the content of insoluble tannin, while the contents of soluble protein and vitamin E decreased gradually, and the overall acceptability score increased first and then decreased. In this study, the comprehensive scoring method was used for dried persimmon slices. The optimal microwave power for IMD persimmon slices was determined to be 490 W, which could effectively improve the drying rate and nutritional value, and has good sensory acceptability.

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In recent years, there has been an increasing interest in dried fruits, despite the fact that many of their nutritional components are easily lost during the drying process. The novelty of this paper was to evaluation the effect of intermittent microwave drying (IMD) on the nutritional quality and drying characteristics of persimmon slices. Persimmon slices were treated with IMD at the microwave power levels of 280, 350, 420, 490, and 560 W, and the drying characteristics and nutritional components such as soluble sugar, soluble protein, and other nutrients were determined and analyzed. The results showed that the drying process of persimmon slices could be divided into three stages; increasing speed, constant speed, and decreasing speed. Meanwhile, the higher the microwave power, the shorter the drying time and the higher the drying rate. The critical point of moisture content in the drying process was between 80.28%~157.56% on a dry basis moisture rate. With the increase of microwave power, the contents of soluble sugar, soluble tannin, vitamin C, and ash increased gradually, but had no obvious effect on the content of insoluble tannin, while the contents of soluble protein and vitamin E decreased gradually. In this study, the comprehensive scoring method was used for dried persimmon slices. The optimal microwave power for IMD persimmon slices was determined to be 490 W, which could effectively improve the drying rate and nutritional value. Therefore, it is concluded that IMD is a potential method for obtaining high-quality dried persimmon slices.