Comparative study on the difference of saponins and nutrients in <i>Panax notoginseng</i> powder dried by new rapid drying technique and traditional hot air

Panax notoginseng (Burk.) F. H. Chen (PN), commonly known as PN, is a nutritious natural food with a long history of consumption and has traditionally been used for dietary purposes in the form of dried processed products. Currently, developed a dry processing at short time and room temperature (DRST), which is characterized by high efficiency and low cost. However, there are few studies on the impact of DSRT. In this study, the effects of conventional hot air drying (DHA) and the innovative drying technology DSRT on the key components of PN were evaluated for the first time. The results showed that DRST could obtain processed PN products with smaller particle sizes and that DRST-treated PN could increase the content of five saponins by 1.38% for Ginsenoside Rg1, 0.1% for Ginsenoside Re, 0.83% for Ginsenoside Rb1, 0.16% for Ginsenoside Rd, and 0.36% for PN saponin R1, relative to the content of five saponins that could be increased by conventional DHA. The metabolome results yielded a total of 1401 metabolites identified and analyzed, and 201 metabolites showed significant differences between the two techniques, which were expressed as amino acids, flavonoids, and other nutrient-active components. The results of this study indicate that the PN products produced by DRST technology have higher nutritional quality compared to traditional processing. This study provides support in the processing of PN and the development of PN products.