Acetoin production in Saccharomyces cerevisiae wine yeasts.

One hundred strains of Saccharomyces cerevisiae were examined for the capacity to produce acetoin in synthetic medium and in grape must. The low production of acetoin was found to be the more common pattern in this species. Most strains exhibited a similar distribution in both media, production ranging from non-detectable amounts to 12 mg l-1. Only four strains produced high quantities of acetoin, up to 29.5 mg l-1 in synthetic medium and up to 194.6 mg l-1 in grape must. This biometric study showed the existence of two phenotypes, "low and high acetoin production", that could be selected for conferring a desirable flavour of the final product.