Evaluation of Anti-Inflammatory, Antidiabetic, Antioxidant, and Anticholinergic Activities, as Well as Chemical Composition and Polyphenolic Compounds in Novel SCOBY-Fermented Juices

Fermentation processes, which occur under the influence of multiplying microorganisms, lead to the creation of products with beneficial health properties. Due to the growing interest of consumers in beverages with health-promoting properties, new raw materials and their processing methods are being intensively studied to obtain products with improved functional values. The purpose of the study is to determine the effect of fermentation using SCOBY (Symbiotic Culture of Bacteria and Yeast) on the chemical composition, polyphenolic profile, and biological activity of apple and pear juices. The fermentation process caused a decrease in the content of polyphenols in apple juice from 1568.8 to 1269.0 mg/L, while in pears, an increase was observed from 492.9 to 576.7 mg/L. Statistically significant changes were observed in the content of individual groups of polyphenolic compounds. The fermentation process also influenced the increase in the value of anti-inflammatory, antioxidant, antidiabetic, and anticholinergic activity. This indicates that fermentation can be an effective process in increasing the biological properties of fruit juices. This fact can be used in the prevention of lifestyle diseases and in the production of functional foods with targeted health-promoting properties.