Fig. 1.

Fermentation performance of yeasts Ethanol Red™ and PE-2 in SM and molasses-based media. Comparison between the ethanol yield (in % of maximum theoretical yield) and ethanol titer (in g l⁻¹). A Ethanol Red™ ethanol yield, B PE-2 ethanol yield, C Ethanol Red™ ethanol titer and D PE-2 ethanol titer. The fermentations were performed using the SM and molasses-based media (Mol_1, Mol_2 and Mol_3) throughout 4 consecutive cycles, simulating the Brazilian ethanol production process. The yeast biomass was kept within 10% (w/w; wet basis), and an acid wash (pH 2.5, 1 h incubation at room temperature) was performed before each new round of fermentation from the second cycle onwards. The tubes were incubated at 30 °C for 7 h and overnight at room temperature. The fermentations were performed in triplicate. For ethanol yield values letters indicate if averages are statistically similar (equal letters) or different (different letters)