The factorial ANOVA indicated that the pre-treatment time had no significant influence (p ¼ 0.088) when evaluated as a single effect and considering all the types of pre-treatment being studied. In contrast, the pre-treatment type had a highly significant effect (p 0.001) on sugar yield when all pre-treatment times were considered. Finally, the interaction between the effects ‘pre-treatment time x pre-treatment type’ turned out to be highly significant (p 0.001). The major change in the saccharification yield occurred when the type of pre-treatment changes rather than when the time of treatment changes. This does not mean that the time is not significant, but the variance produced by its effect is lower than the variance produced by the pre-treatment type. The pre-treatment time had a high impact on saccharification yield within each pretreatment type (Figs. 1e3).