An improved saccharification process comprises the use of a glucoamylase and at least one cellulase. The improved saccharification process results in improved yields of fermentations products, such as ethanol. In one embodiment, the improved saccharification process results in an increased yield of up to 0.5% to 1% ethanol using commercially available cellulases. Also provided are improved simultaneous saccharification and fermentation (SSF) processes, and compositions comprising a liquefied starch slurry, a glucoamylase, and a cellulase.