Preparation and physicochemical characterization of persimmon fermented beverage obtained by spontaneous and inoculated fermentation
The aim of this work was to develop and evaluate physicochemical characteristics, their viability, and which is the most appropriate process to produce persimmon fermented beverage, obtained by three treatments, namely: spontaneous and inoculated fermentation with commercial Saccharomyces cerevisiae yeasts (Fleishmann baker yeast and CA-11). Persimmon pulp was diluted in water in a 1:1 ratio (v/v) and chaptalized to a soluble solids content of 24°Brix. Potassium metabisulfite was used as bacterial growth inhibitor and antioxidant. Bentonite was used as fining agent to clarify the wine. All fermentation processes were conducted under the same conditions at 28°C, consisting of spontaneous fermentation and inoculated fermentation with Fleishmann yeast and CA-11. Must aliquots were collected daily to monitor cell population, soluble solids and pH. At the end of fermentation, beverages were transferred to clean containers, removing excess sediment. Afterwards, beverages were subjected to filtration and pasteurization. The following analyzes were performed: sugars (glucose, fructose and sucrose), alcohols (ethanol, methanol and glycerol), ethanol yield and total acidity. Yeast population was held adequate during the fermentation process. Fermentation processes conducted with commercial yeasts were more viable due to higher ethanol yields when compared to spontaneous fermentation. CA-11 yeast proved to be the most suitable for persimmon fermented beverage production due to lower residual reducing sugar contents.