Production of fermented kefir beverage from butterfly pea flower extract (Clitoria ternatea L.)

Abstract

Butterfly pea (Clitoria ternatea L.) flowers are rich in anthocyanins, flavonoids, and polyphenolic compounds that exhibit strong antioxidant and health-promoting properties. This study aimed to develop a fermented functional beverage from butterfly pea flower extract using water kefir grains as a natural probiotic. The fermentation process was optimized by evaluating sucrose concentration, kefir grain ratio, and fermentation time. Physicochemical characteristics, microbiological quality, and sensory attributes of the final product were also assessed. The results showed that fermentation conditions significantly influenced the beverage’s chemical composition and sensory properties. The optimal fermentation conditions were obtained with a kefir grain ratio of 6% (w/v) and a fermentation time of 48 h, producing a beverage with balanced acidity and desirable sensory characteristics. The final product exhibited a pH of 3.53, ethanol content of 0.52% (v/v), total acidity of 0.23%, and total polyphenol content of 170 mg/L, while meeting microbiological safety standards. Sensory evaluation indicated good consumer acceptance, with overall scores corresponding to the hedonic level of “slightly liked” to “liked”. These results demonstrate the potential of butterfly pea flower extract as a substrate for producing fermented probiotic beverages with promising functional and nutritional benefits.