Effects of Different Aging Treatments on Functional Components and Flavor Substances of Chrysanthemum Rice Wine

Three methods including ultrasound (US), microwave (MW), and a combination of ultrasound and microwave (SW), were used to treat rice wine and chrysanthemum rice wine for 3 and 7 d respectively. The basic physicochemical indicators, antioxidant activity, flavor substances, and sensory evaluation of wine samples were analyzed to explore the effects of different aging treatments on the functional components and flavor substances of chrysanthemum rice wine. The results showed that after 7 d of microwave treatment, the highest reducing sugar content of 112.92±7.39 mg/mL was detected in chrysanthemum rice wine. The total acid content of the samples increased under three different aging methods. Ultrasound treatment for 7 d significantly increased the total acid content in chrysanthemum rice wine (P<0.05). After 3~7 d of microwave treatment, the polyphenol content of both rice wine and chrysanthemum rice wine increased, while the flavonoid content increased under ultrasound treatment conditions. Analysis of antioxidant activity showed that compared with the control group, microwave treatment for 7 d had the greatest effect on the DPPH clearance of chrysanthemum rice wine, decreasing from 60.49%±0.04% to 19.69%±1.78% (P<0.05). The ABTS⁺ clearance rate of chrysanthemum rice wine increased after 3 d of ultrasound and microwave combined treatment, while the ABTS⁺ clearance rate decreased under other treatments. All three methods improved the FRAP of the sample, and microwave treatment for 7 d had the highest total antioxidant capacity of FRAP. During the aging process, the free radical scavenging rate and total antioxidant capacity of chrysanthemum rice wine were stronger than those of rice wine. GC-MS results showed that the types and relative contents of flavor substances in chrysanthemum rice wine decreased under three different aging treatments, but isobutanol increased under different conditions; After 3 d of ultrasonic microwave combined treatment, the relative content of ethyl palmitate increased significantly. The relative content of 3-hydroxy-2-butanone increased under three treatments of chrysanthemum rice wine. Ultrasound treatment for 3 d had the best retention effect on the flavor substances in chrysanthemum rice wine, with 34 flavor substances. The sensory evaluation results showed that after 3 d of combined treatment with ultrasound and microwave, the taste of chrysanthemum rice wine was harmonious and presented a floral honey flavor. Indicating that suitable aging methods can enrich the flavor substances, balance the nutritional components, and improve the taste of chrysanthemum rice wine.