Assessing White Hibiscus Calyces as a Potential Ingredient for Kombucha

Kombucha’s growing popularity worldwide has been accompanied by a growing consumer interest in exploring new flavors and adopting healthier diets. In this preliminary consumer-driven study, we investigated the application of white hibiscus (WH) calyces in the development of novel kombucha beverages. Kombuchas were made from 100% black tea (BT), 100% WH, and 50% BT/WH blend infusions, then their pH, total titratable acidity (TTA), ethanol content, sucrose, glucose, and fructose concentrations were measured. Untrained sensory participants (N = 97) rated the kombuchas using a 9-point hedonic scale, described them using a check-all-that-apply list of attributes, and answered a willingness-to-pay (WTP) question. Tea infusion and fermentation time had a significant effect on pH, TTA, ethanol, sucrose, fructose, and glucose content (p < 0.05). High residual sugar levels observed in the WH kombucha indicated sluggish fermentation. Kombuchas differed significantly in overall-liking, color, aroma, flavor, and mouthfeel liking, and WTP (p < 0.05). Overall, BT kombucha was preferred over the WH kombuchas (100% and blend). Sensory attributes “refreshing”, “floral”, “hibiscus”, “fruity”, and “sweet” were positive drivers of acceptability, while “pungent” and “astringent” were negative drivers. Results suggest that blends containing less than 50% WH may provide more appealing sensory attributes to consumers, and that further study is needed.