The first step of the statistical approach to the analysis
optimization was to establish the criteria that will define
the experimental factors that have a significant effect on
the response variables. Therefore, to optimize the ethanol
production it was first performed as a 24 factorial design.
Four relevant factors for the fermentative process were
selected in a factorial design 24. The variables, studied
simultaneously were: TRS concentration in sugar cane
molasses (150 and 250 g L1), temperature (25 and
35 C), agitation (180 oscillations per minute and static culture)
and culture time (12 and 24 h), as shown in Table 1.