Fatty acids derived from biomass at a step in a fermentation process can be added to a fermentation medium comprising a recombinant microorganism that produces a product alcohol. At least one of growth rate and fermentable carbon consumption of the microorganism is greater in the presence of the fatty acids than the growth rate and the fermentable carbon consumption of the microorganism in the absence of the fatty acids. The addition of the fatty acids can increase glucose consumption, and can improve microorganism biomass production (cell growth/density) and growth rate, thereby reducing production time and increasing productivity of the fermentation process.
