Vinasse production is one of the most significant and challenging issues in the industrial production of ethanol due to pollution problems. In this study, vinasse obtained from ethanol by fermentation of sugarcane molasses was used instead of water to prepare the fermentation medium. Saccharomyces cerevisiae F-727 was selected from 10 tested yeast strains. Nutritional requirements of nitrogen, phosphorous and magnesium, as well as the effect of inoculum size were studied. There was a decrease in required nutrients when vinasse was used instead of fresh water; and 50% yield was achieved in fresh water together with an improved efficiency of the fermentation.
Key words: Vinasse, ethanol fermentation, Saccharomyces cerevisiae.