Application of the Super-modified Simplex Optimization Method in the Fermentation of Butiá Palm (Butia eriospatha (Martius) Beccari) Aqueous Extract

The aim of this study was to determine the best conditions for alcoholic fermentation of butia pulp aqueous extract using experimental mixtures with restrictions and simplex optimization. Yeast concentration, yeast extract concentration, and NH4H2PO4 concentration were used as the independent variables, with the ethanol production yield as the response. The validity of the model for predictive purposes was confirmed by analysis of variance, it was significant (p = 0.001), presenting an experimental coefficient of determination (R 2 ) of 0.97, adjusted R 2 of 0.89, and non-significant lack of fit (p = 0.1082). The simplex optimization indicated a formulation containing 4.0 g L -1 yeast extract, 5.65 g L -1 yeast and 0.35 g L -1 NH4H2PO4 for the optimum yield of ethanol production (66.75%). In order to validate the predictive equation, the assay was repeated in triplicate under the optimum conditions, resulting in an average yield of 68.29%. Applying the t-test, it was found that there was no significant difference (p = 0.4552) between the mean value and that obtained by simplex optimization.