According to our knowledge,there is a scarce number of investigations indicating the use ofS. cerevisiae strains for the valorization of OMWs or OMW-basedmedia for the production of ethanol. The originality of our studyis based upon the simultaneous presence of molasses and OMWs(not pre-treated) as substrate and the growth of the strain usedunder completely non-aseptic conditions. The rationale of the uti-lization of these blends is that it was desirable to study the effect ofthe utilization of these mixtures of residues upon the physiologicaland kinetic behavior of the strain, since in a scale-up of the pro-cess in large-scale operations, OMWs could be used as tap watersubstitute for molasses dilution. To further reduce the bioprocesscost, fermentations under completely non-aseptic conditions wereconducted. Media presenting various initial phenolic and sugarcontents were formulated and the ability of the strain to produceethanol and biomass together with the simultaneous reduction ofthe color and the phenol content of the medium was investigatedand comprehensively discussed.