Preliminary experiments to determine the concentration of SM
that would provide the best yield (Y2), higher ethanol productivity
(P) and lowest concentration of residual sugar (RS) were performed
under conditions of natural soybean molasses fermentation with no
enzymatic hydrolysis. The kinetic profiles of substrate consumption
and ethanol production, the amount of cells and a central composite
design (CCD) that evaluated the influence of the concentration of
SM and inoculum in the responses mentioned above were all determined.
The CCD in the concentration of SM ranged from 520.0 g/L to
180.0 g/L and the concentration of inoculum ranged from 18.0 g/L
to 52.0 g/L. An alpha orthogonality of 1.147 was used in planning.