Myrtle (Eugenia gracillima Kiaersk.) as a fermented alcoholic beverage alternative to wine: Preliminary study

Abstract

Myrtle (Eugenia gracillima Kiaersk.) is an underexploited fruit rich in bioactive compounds. It can be consumed fresh or processed into diverse products. This preliminary study aimed to develop myrtle-based fermented alcoholic beverages and evaluate the effects of different concentrations of total soluble solids (TSS), in which B1 (15 °Bx) and B2 (20 °Bx). Fermentation kinetics, fermentation yield, alcohol yield, productivity, physicochemical, phytochemical and color properties were determined. In addition, color degradation kinetics and correlation analyze (significant phytochemical and color parameters) were performed. A second-order polynomial model provided a good fit to fermentation data (R2 > 0.95). Fermentation of myrtle must with a lower TSS content resulted in higher fermentation yield (60.00%) and provided a beverage whose physicochemical parameters were within regulatory limits. Myrtle beverages were excellent sources of phenolic compounds (3478.66–3783.04 mg gallic acid equivalents 100 g−1). The beverage with higher TSS had a significantly stronger color (p ≤ 0.05). Color degradation kinetics were described by first-order (B1) and zero-order (B2) models, which revealed that redness (a*) was the most sensitive color parameter. There was a significant negative correlation (p ≤ 0.05) of most color parameters with phenolic compounds values, indicating that darker colored formulations have higher content of these phytochemical compounds. Industrial production of alcoholic fermentation of myrtle beverages is feasible and may represent an interesting income source for small-scale producers.