Development and Characterization of Kombucha-Based Functional Beverage: Physicochemical, Nutritional, Antioxidant and Sensory Evaluation

Abstract Kombucha is an alcoholic beverage based on fermented tea produced by symbiosis between bacteria and yeast (SCOBY). The purpose of this research was to produce a sweet black tea beverage through kombucha and to evaluate its physical, chemical, nutritional, antioxidant, and sensory attributes during the process of fermentation. The black tea infusion was produced by soaking 5 g of tea leaves in 1 liter of distilled water, sweetening it with 100 g of sugar, cooling it to room temperature, adding SCOBY, and fermenting it for 7-10 days at 25-28 °C. The pH, total soluble solids (TSS), and antioxidant activity were monitored at days 0, 3, 7, and 10. pH decreased from 5.50 ± 0.05 to 3.20 ± 0.02, whereas TSS decreased from 12.00 ± 0.10 to 7.00 ± 0.06 °Brix. Antioxidant activity increased from 18.00 ± 0.50% to 52.00 ± 0.80%. The beverage contained 94.50 ± 0.20% moisture, 0.30 ± 0.02% protein, 0.10 ± 0.01% fat, 4.80 ± 0.15% carbohydrate, and 0.30 ± 0.02% ash, with an estimated energy value of 20 kcal/100 mL. The sensory evaluation by a nine-point hedonic scale resulted in an overall acceptability score of 8.30 ± 0.27. The results showed that the fermentation under controlled conditions caused significant differences in the physicochemical and antioxidant properties, and it also led to a highly acceptable Kombucha beverage.