Design and development of a mixed alcoholic beverage kinetics using asaí (Euterpe precatoria) and copoazú (Theobroma grandiflorum)

Copoazú (Theobroma grandiflorum), a fruit from the same genus as cacao, and asaí (Euterpe precatoria) a palm fruit, both of Amazonian origin, could promote local economic growth through fruit processing to increase the added value. This study aimed to identify the kinetics of alcoholic fruit beverages made from copoazú and asaí pulp or seeds, i.e., the fermentation kinetics in the case of copoazú drinks and the diffusion kinetics in the case of asaí drinks. Additionally, the feasibility of generating a milky mixture with the liquor obtained from the copoazú fruit processing was evaluated. Statistical analysis was performed by ANOVA tests and modeling of kinetics parameters with an evolutionary algorithm and optimization. Copoazú pulp was fermented with 15% Prestige Turbo Yeast®. Fermentation was separated into two stages: controlled fermentation during the first 5 d and a maturation process in the following 25 d. According to the modeling, the greatest efficiency was observed with 600 g L-1 pulp concentration and soluble solids adjusted at 35°Brix, with alcohol contents of up to 20% (w/v) after 30 d of processing and evidence that there may be inhibition of fermentation due to glycerol. The whole fruit and pulp of asaí were extracted with ethanol to obtain a liquor with the micronutrients and flavors of the fruit, and the anthocyanin content was used as a degradation process marker. Modelling showed that the optimum point that yielded maximum anthocyanin concentration was achieved at 60 d of maturation by extracting pulp in a 45% (w/v) ethanol solution resulting in a maximum anthocyanin content of 94.2 ± 15.3 mg of cyanidin-3-glucoside kg-1 of liquor. After that, a degradation process was observed as anthocyanin content diminished.