The Effect of Adding Exogenous Bletilla Striata Polysaccharide on Kiwifruit Wine Quality

Kiwifruit wine is valued for its nutrients and health benefits, but conventional brewing often results in a weak aroma due to precursor insufficiency and oxidative losses during fermentation. Therefore, adding natural polysaccharides with antioxidant and metabolic regulatory properties prior to fermentation may be a promising quality improvement strategy. Bletilla striata polysaccharide (BSP), a plant polysaccharide with multiple bioactivities, may have the potential to regulate kiwifruit wine quality. This study explored the regulatory effects of 100–400 mg/L BSP on the physicochemical properties, antioxidant activity, and aroma compounds of kiwifruit wine, which suggested its possible mechanism of action at the metabolite level. The results showed that the 300 mg/L BSP treatment achieved the best overall quality, maximizing the DPPH and ABTS radical scavenging rates and increasing the total relative abundance of volatile compound concentration by 28.69% compared with the control. Electronic nose testing, odor activity value analysis, and sensory evaluation all indicated that the 300 mg/L BSP group exhibited the best overall aroma profile, and non-targeted metabolomics further suggested that the 300 mg/L BSP addition was associated with the depletion of quinic acid, the accumulation of aromatic amino and succinic acids, and changes in lipid-related metabolites, which were correlated with enhanced aroma production. In conclusion, exogenous BSP addition appears to improve kiwifruit wine quality, and this study provides a theoretical basis for its application in fruit wine brewing.