Response Surface Optimization of Mesona Microwave Intermittent-Hot Air Combined Drying Process and Its Effect on Mesona Gel Quality

Abstract

Taking Mesona blumes as the research object, the effects of microwave power, microwave intermittent time, drying point and drying temperature on the extraction rate of polysaccharides were studied with the microwave intermittent hot air drying method. The effects of different drying methods on the extraction rate and gel quality of Box-Behnken were studied. The results showed that the optimal process was as follows: The microwave power was 403 W, the microwave intermittent time was 60 s, the moisture content at the conversion point was 42%, the hot air drying temperature was 74 ℃, and the extraction rate of Mesona blumes polysaccharide was 13.60%. The extraction rate of polysaccharides from the microwave intermittent hot air drying was higher than the heat pump dried (12.36%) and sun- cure dried (12.78%). The drying time was only 1.44% to 16.67% of the latter two drying methods. The hardness of the gel samples (516.60±8.54) g, elasticity (0.83±0.01) and recovery (0.33±0.01) were all moderate. In the gel the cohesion (0.48±0.01) was slightly smaller, the adhesive viscosity (359.68±11.56) g and chewiness (285.54±13.21) g were higher, and the texture characteristics and sensory score of the gel samples were better. Comprehensive comparison, the microwave intermittent-hot air combined drying was more suitable for Mesona blumes drying.

Keywords

• mesona blumes
• microwave intermittent-hot air combined drying
• process optimization
• extraction rate of polysaccharide
• gel quality