The overall process efficiency in the tested samples are in the range 7.21-10.60 g ethanol each 100 g raw material
(DM). The best results was obtained in CP016, even with the worst fermentation performance, probably due to
inhibitors formation during high severity parameter pre-treatment conditions. Double-step samples reached higher
efficiencies with low severity parameter values (4.2-4.3) and longer treatment time in the first pretreatment step.