Impacts ofnon-Saccharomycesspecies and aeration on sequential inoculation withSaccharomyces cerevisiaeto produce lower alcohol Merlot wines from Washington state

BACKGROUND Species of non-Saccharomycesyeasts isolated from Washington vineyards were evaluated for their abilities to reduce alcohol contents of wines. As many of these yeasts benefit from some oxygen, the effect of limited aeration was also studied. RESULTS Although fermentations of a high sugar Merlot grape must (310 g L-1) did not reach dryness, inoculation ofMetschnikowia chrysoperlae,Mt. pulcherrima,Meyerozyma guillermondii,Pichia kluyveri, orP. membranifaciensyielded in wines with lower amounts of ethanol without excessive levels of acetic acid. Aeration frequently resulted in wines with less ethanol but with more acetic acid compared to non-aerated fermentations. Inoculation ofMt. pulcherrimaorMy. guilliermondiiinto another Merlot grape must that contained a lower initial amount of fermentable sugar (266 g L-1) resulted in dry wines that contained less alcohol. CONCLUSIONS Inoculation ofMy. guilliermondiiorMt. pulcherrimabefore primary alcoholic fermentation resulted in wines with reduced alcohol contents without excessive acetic acid production. (c) 2020 Society of Chemical Industry