DEVELOPMENT AND CHARACTERIZATION OF A KOMBUCHA-LIKE FERMENTED BEVERAGE FROM GREEN COCONUT SOLID ALBUMEN (Cocos nucifera L. var. nana)

The liquid albumen of coconut, popularly known as “coconut water,” is widely consumed both fresh and industrialized due to its pleasant flavor, refreshing properties, and nutritional value. However, the growing demand for this beverage generates large amounts of residues, particularly the solid albumen (green coconut pulp), which, despite its favorable sensory and nutritional characteristics, is often discarded. Thus, the utilization of this by-product emerges as a sustainable and economically viable alternative, with fermentation representing a promising strategy. In this context, the present study investigated the technical feasibility of producing a kombucha-like fermented beverage from the solid albumen of green coconut (Cocos nucifera L. var. nana), aiming to add value to this agroindustrial residue. Three formulations were developed using solid albumen at different maturation stages (E1, E2, and E3). The process began with the preparation of aqueous extracts at a 1:15 (w/v) ratio, followed by heating up to 60 °C for partial fat removal using an industrial cream separator, and subsequent cooling to 15 °C. Sucrose was then added until 5 °Brix was reached. Each extract was inoculated with 3% of a symbiotic culture of bacteria and yeasts (SCOBY) and 10% of fermented Camellia sinensis tea (starter). Fermentation occurred in two stages: the first at 28 °C for 48 h in a BOD incubator, and the second until gas formation, with soluble solids adjusted before the second fermentation. Samples were analyzed for microbiological (Escherichia coli, Salmonella spp., Enterobacteria, coagulase-positive Staphylococcus, molds, and yeasts), physicochemical, and bioactive parameters. All formulations complied with the microbiological requirements established by Brazilian legislation, confirming their safety for human consumption. Physicochemical analysis revealed significant differences in acidity and phenolic compound content among the formulations. The E1 formulation, derived from the youngest albumen, exhibited the highest total phenolic content (32.10 mg GAE/100 mL) and the strongest antioxidant potential, indicating greater biological and functional activity. These findings demonstrate that solid green coconut albumen can be sustainably utilized in the production of functional fermented beverages, expanding the range of applications for agroindustrial by-products and contributing to the development of innovative plant-based products. The E1 formulation stood out as the most promising, with potential for commercial applications and further investigations focused on shelf stability, economic feasibility, and sensory acceptance. Overall, this study highlights the potential of transforming a low-value by-product into an innovative functional beverage, emphasizing the role of applied research in promoting sustainability and technological innovation in the food sector.