The Effect of the Addition of Spirulina spp. on the Quality Properties, Health Benefits, and Sensory Evaluation of Green Tea Kombucha

Kombucha is a beverage that is gradually becoming popular worldwide because of its health benefits. The addition of Spirulina spp., a biomass abundant in nutrients and bioactive compounds, improved the quality properties, health benefits, and sensory evaluation of green tea kombucha products. The findings indicate that the original Spirulina spp. powder promoted the proliferation of advantageous microbes in SCOBY at the optimal time after the 12 fermented days. Therefore, improving the physiochemical and biochemical characteristics of the final kombucha product. The maximum concentration of total titratable acid, protein, phenolic, and flavonoid compounds is achieved with the addition of 0.6% Spirulina spp. powder. The addition of Spirulina at the 0.8% ratio not only reached the highest number of useful microbes but also provided better health benefits, including antioxidant, antibacterial, proteolytic, and lipolytic activities. However, the result of the sensory evaluation showed the green tea kombucha with 0.6% Spirulina spp. is rated higher in gustatory, tactile, and overall. These promising results confirmed that kombucha green tea with Spirulina spp. might become a potential functional beverage that satisfies consumer demand for healthy fermented products made from non-animal resources. Graphical Abstract Highlights OSp improved the quality characteristics, health benefits, and sensory evaluation of GtK. The ratios of 0.6 and 0.8% OSp were the optimal ratios for the best quality characteristics and health benefits on the 12 th day of the fermentation process. The ratio of 0.6% OSp was the optimal ratio for the best sensory evaluation results (visual, olfactory, gustatory, tactile, and overall).