Effect of intermittent microwave drying on nutritional quality and drying characteristics of persimmon slices

Abstract

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.

Effects of pre-processing on the active compounds before drying Eucommia ulmoides leaves

“…Steaming and frying, are the traditional ways in China to process green vegetable or tea products. Air heating with electric ovens and microwaves has also been used to process plants in recent years (Rocha et al, 2011;Thamkaew et al, 2021;Qin et al, 2022). The microwave process is considered a better method as it can avoid browning, reduce drying duration, and control undesirable biotransformation in foods (Rodríguez-Lora et al, 2022;Vadivambal & Jayas, 2007;Aydar, 2021).…”