The performance of Saccharomyces cerevisiae MBG3964, a strain able to tolerate >18% v/v ethanol, was compared to leading industrial ethanol strain, Fermentis Ethanol Red, under high gravity corn mash fermentation conditions. Compared to the industrial ethanol strain, MBG3964 gave increased alcohol yield (140 g L(-1) vs. 126 g L(-1)), lower residual sugar (4 g L(-1) vs. 32 g L(-1)), and lower glycerol (11 g L(-1) vs. 12 g L(-1)). After 72 h fermentation, MBG3964 showed about 40% viability, whereas the control yeast was only about 3% viable. Based on modelling, the higher ethanol tolerant yeast could increase the profitability of a corn-ethanol plant and help it remain viable through higher production, lower unit heating requirements and extra throughput. A typical 50 M gal y(-1) dry mill ethanol plant that sells dried distiller's grain could potentially increase its profit by nearly $US3.4 M y(-1) due solely to the extra yield, and potentially another $US4.1 M y(-1) if extra throughput is possible. (C) 2011 Elsevier Ltd. All rights reserved.