Juice Dilution Affects Haskap (Lonicera carulea L.) Wine Fermentation Completion and Wine Chemistry

Haskap (Lonicera carulea L.) has been widely used in medicine because of its health benefits to humans. Contrarily, despite growing interest in fermentative applications, haskap wine studies are extremely limited. Due to the high pigmentation of haskap juice, a fermentation experiment with different prefermentative juice dilutions was conducted to discover the influence of dilution on haskap wine fermentation and final wines. Four treatments, including 1:1, 1:2, 1:4, and 1:5 juice-to-water ratios, were applied in this research. The results indicated that water quantities for dilution may influence the fermentation completion rate. Concerning final wines, the 1:1 dilution ratio had significantly lower pH and lower ethanol but higher acidity and glycerol compared to the other three treatments. With increasing dilution, the final wine color variation increased relative to the initial must color. Antioxidant activities in the final wines were all reduced compared with the corresponding initial must metrics. The total phenolic profiles indicated dilution largely influenced total anthocyanins followed by total flavonols while having limited influence on the total hydroxycinnamates and total flavanols in haskap wines. With anthocyanin compounds as the main coloring components detected in haskap wines, future research may focus on haskap nutrients and quality maintenance during primary fermentation and throughout aging processes. This work pioneered haskap wine fermentation with different juice materials. Continued work with additional optimization strategies may help fine-tune the fermentation procedures for haskap fruit applications.