Study on microwave vacuum drying characteristics and quality of seed melon solids

In order to explore the best process parameters of microwave vacuum drying of seed gourd, taking Gansu Baiyin “seed gourd No.1” as the test material, the homemade microwave vacuum equipment for drying seed gourd solids test was used to explore the drying temperature, vacuum degree and specific power on the drying characteristics and physicochemical quality of dry products. The results showed that with the increase of drying temperature and vacuum degree, the decrease of specific power, the decrease rate of material moisture ratio increased and the drying efficiency improved. The effective moisture diffusion coefficient of seed melon solids ranged from 0.700 74×10^-9～4.565 79×10^-9 m~2/s and increased with the increase of drying temperature, vacuum degree and specific power. The highest contents of polysaccharide（105.44 mg/g）, VC（1.21 mg/g） and dietary fiber（80.69%） with high rehydration ratio（4.23） and bright color were obtained at the drying temperature of 50 ℃, vacuum degree of-0.070 MPa and specific power of 20 W/g in the samples. Taken together, microwave vacuum drying can better guarantee the comprehensive quality of seed melon solid and improve the added value of products. This study can provide a theoretical reference for the development of the potential value and industrial processing of seed melon solid.