Komb ucha is usually made from tea leaves (Camellia sinensis L.) extracts added with sugar which is fermented with kombucha starter symb iotic culture of b acteria and yeast (SCOBY) containing. Acetob acter xylinum and yeasts including Saccharomyces cerevisiae. In addition to tea leaves, leather dried coffee (cascara) can b e harnessed into b everages like tea steeping. This research aims to ferment cascara tea b y SCOBY and characterize the cascara komb ucha. These research use two factors i.e. cascara concentrations (1 and 2% b /v) and fermentation periods (4, 8, 12, and 16 days). Sugar was dissolved into water and b oilled, added with the cascara while stirring for ab out 5 minutes, filtered and cooled to 40°C, and then fermented in glass jars with faucets indoor without exposure to direct sunlight for 4, 8, 12, and 16 days. The results showed that concentration of cascara and fermentation time affected the characteristics of cascara kombucha. The effectiveness tests showed that cascara komb ucha made from 1% b /v cascara fermented for 8 days resulted in the b est and most preferred komb ucha. The komb ucha characteristics include dissolved solid content of 11.25°Brix, specific gravity of 1.01 g/mL, viscosity of 0.9 cP, b rightness (L) 42.0, reddish color (a) 15.1, yellowish color (b) 28.88, pH 3.43, total acid of 0.29, phenolic of 9.9 mg GAE/mL. The komb ucha flavor was slightly acidic, murky in color, with slight b itter taste.

Abstract. Urbahillah A, Jayus J, Nurhayati N. 2021. Improving SCOBY starter using co-culture of tapai and bakery yeast. Biodiversitas 22: 4617-4624. Kombucha is a beverage fermented by a symbiotic bacteria and yeast known as SCOBY (Symbiotic Culture of Bacteria and Yeast). Bacteria and yeast contribute to the formation of organic acids, aroma, taste, and flavor of kombucha. The commercial yeasts used in Indonesian are baker’s yeast and tapai yeast. This study was conducted to develop SCOBYco-culture with tapai yeast and baker’s yeast and evaluate its activity. The ingredients for the kombucha were cascara, water, and sugar, which were fermented with three formula starter, i.e. original SCOBY 10% w/v (SN), co-culture SCOBY 10% w/v with 0.1% w/v of baker’s yeast (SNR), and co-culture SCOBY 10% w/v with tapai yeast 0.1% w/v (SNT). The starter activity were determined based on the OD (Optical Density) value. Yeast screening was carried out on the dominant starter population. Furthermore, morphologically yeast was identified based on colony type, color, and shape of cell. Then yeast was identified by their fermentation profile using API 20C Aux Kit. Isolate A showed white colony with convex elevation and the cell was round-shaped. Colony of isolate B and isolate C were creamy in color and oval cell shaped. The API results revealed that the first isolate was identified as Candida famata, second isolate was as Candida krusei, and the third isolate was as Candida magnoliae. Three types of fungi were found from SCOBY, namely Mucor sp., Trichoderma sp., and Fusarium sp. Mucor sp. has non-septate hyphae, and round black spores. Trichoderma sp. has septate hyphae, greenish-white spores, and the conidia have the shape of globose to ellipsoidal Fusarium sp. has a mold with septate hyphae, yellowish-white colonies, and the conidia have the shape of obovoid. Bacteria, yeast, and mold present in the medium form a powerful symbiosis for produce metabolite.