Effect of Nitrogen, Agitation, and Temperature on Fermentation Kinetics and Volatile Profile of an Agave Juice-Based Beverage

This study evaluated the effects of nitrogen source, temperature, and agitation on fermentation performance and volatile compound formation in an agave juice-based beverage fermented with Saccharomyces cerevisiae. Agave juice contained a high concentration of reducing sugars (156.69 g/L), representing 83.16% of the total sugars, predominantly fructose, and a low assimilable nitrogen concentration (0.069 g/L), indicating nitrogen limitation. Fermentation assays were performed at 18 and 28 °C under static or agitated (100 rpm) conditions, with inorganic or organic nitrogen supplementation. At 28 °C, organic nitrogen supplementation under static conditions increased ethanol production to 72.26 g/L. At 18 °C, fermentation kinetics were markedly slower, but nitrogen supplementation increased ethanol production from 34.25 g/L in the control to 59.89 g/L with inorganic nitrogen, indicating that nitrogen supplementation had a greater relative effect under low-temperature fermentation. Volatile profiling revealed that under static fermentation at 18 °C, organic nitrogen supplementation increased the relative abundance of higher alcohols, particularly 2-phenylethanol, whereas ester formation varied according to both nitrogen source and fermentation temperature. Overall, nitrogen source, agitation and temperature strongly affected both fermentation efficiency and volatile formation, supporting the design of controlled processes to improve aromatic complexity and performance in agave-based fermented beverages.