Effects of different drying methods on physico-chemical properties, bioactive and taste substances of Cynomorium songaricum

Cynomorium songaricum is a typical edible and medicinal plant, also called Suoyang (Chinese name). The effect of different drying methods on Suoyang quality has not yet been performed. Here, four drying methods were tested, including sun drying (SD), microwave drying (MD), hot air drying (HAD), and vacuum freeze drying (VFD), to evaluate the influences of various drying methods on the physico-chemical properties, bioactive and taste substances of dried Suoyang. Results showed that VFD treated samples maintained the original cellular structure and color, and had higher textural properties, antioxidant activities, and rich flavor. In addition, a total of 980 metabolites in four kinds of dried Suoyang were detected and clustered into 9 co-response modules based on utilizing widely targeting metabolomics method and weighted metabolite co-response network analysis (WMCNA). Among the important modules, 3 key metabolites were identified as potential quality markers of overall antioxidant capacity and 30 key metabolites were identified as the main taste substances, which also might be relate to the nutritional value of dried Suoyang. This finding will provide reference for choosing proper drying method that can maintain the quality of dried Suoyang and adapt to industrial production.