RESIDUE (SCOBY) FROM KOMBUCHA BEVERAGE PRODUCTION: CHEMICAL COMPOSITION AND MORPHOLOGY

Kombucha is a slightly sweet and acidic beverage produced from the fermentation of black or green tea (Camellia sinensis). The fermentation process involves a complex community of microorganisms, including yeasts and bacteria, which are inoculated through the addition of a SCOBY (Symbiotic Culture Of Bacteria and Yeast). A SCOBY is a biofilm composed of yeasts that produce ethanol and CO₂ from sugars, and acetic acid bacteria that convert the ethanol into acids (acetic and gluconic). During the fermentation process, the SCOBY grows in successive layers; the longer the fermentation time, the greater the thickness and yield of the biofilm. For each new fermentation, it is recommended to use the most recently formed layer from the previous fermentation, while the older, lower layers are typically discarded in both industrial and domestic settings. Accordingly, the objective of this study is to evaluate the industrial kombucha residue, the SCOBY, to assess its potential for application. The contents of moisture, ash, lipids, proteins, fibers, and dry extract were determined. The morphology was evaluated by scanning electron microscopy (SEM). The SCOBY is predominantly composed of moisture 96.40 ± 0.25%. Its dry matter fraction consists primarily of fibers, with 46.28 ± 2.59% for neutral detergent fiber and 45.54 ± 2.64% for acid detergent fiber, along with protein 4.13 ± 0.64%, lipids 2.77 ± 0.08%, and ash 0.02 ± 0.00%. Due to the significant insoluble fiber content, it can be stated that SCOBY is a promising source of bacterial cellulose, enabling its application not only in food but also in other products, such as biodegradable packaging. The obtained SEM micrographs corroborate these findings, providing evidence of a fibrous structure suitable for cellulose extraction. Consequently, this study reinforces the importance of utilizing SCOBY for the food industry, whether as a moist ingredient in culinary preparations or as a raw material for the production of sustainable packaging.