Análise de metabólitos em kombuchas caseiras e comerciais por meio de RMN de 1H

Abstract

Kombucha is an ancient, fermented beverage obtained through the action of a symbiotic culture of bacteria and yeast (SCOBY) on sweetened tea. In recent decades, kombucha consumption has grown worldwide, especially in Brazil, due to its potential functional properties associated with bioactive compounds such as polyphenols, organic acids, vitamins, and enzymes. This growing popularity has stimulated artisanal production, resulting in a wide diversity of flavors and preparation methods. This study aimed to investigate how changes in the plant matrix and the type of sugar used in homemade preparations influence the beverage's characteristics, searching for a combination that optimizes its chemical profile. Furthermore, the study measured the total phenolic content in the selected sample and compared the characteristics of homemade kombucha with those of commercial samples. Nuclear Magnetic Resonance (NMR) analyses allowed for the identification of fermentation compounds, such as organic acids, residual sugars, ethanol, and other metabolites, revealing variations in the chemical profile among different samples. Regarding the choice of tea, it was found that the plant matrix alone is not the sole determinant of compound formation. Instead, the metabolite profile showed a strong dependence on the type of sugar used and, notably, on the residual sugar remaining after the process. However, regardless of the combination of these factors, an increase in total phenolic content was evidenced, suggesting an enhancement of the final beverage's antioxidant capacity. In summary, this study demonstrates that kombucha is a complex beverage, sensitive to multiple production factors, such as the SCOBY, tea type, sugar, and seasonality, indicating an increase in antioxidant capacity and potential improvement in probiotic properties.