It was found that neither the enzymes of the grapes nor those of wine yeast Saccharomyces ellipsoideus strain 223 attacked the higher polysaccharides present in corn syrups. The alcohol yield of the corn syrups approached but did not quite reach theoretical assuming that all of the dextrose equivalent (DE) solids were fermented. Glucose, sucrose, and 95 DE corn syrup fermented at about the same rate and yielded comparable alcohol contents. At equal solids content, the 42 DE syrup fermented slower in most cases and yielded lower alcohol content than higher DE syrups.