Natural yeast makes tastier wine

Natural yeasts will be trialled for commercial use in wine making this year, thanks to research from The University of Auckland.

Saint Clair, Delegat’s, Pernod-Ricard New Zealand, Nobilo, Kim Crawford’s and Forrest Estate wineries will be using a newly discovered, naturally occurring New Zealand yeast to ferment grapes from this year’s harvest.

The yeast was discovered as part of a six year Foundation for Research Science and Technology project, looking at the specific characteristics of New Zealand Sauvignon Blanc. New Zealand is regarded as one of the foremost producers of Sauvignon Blanc worldwide, and is very distinctive. The FRST project, headed by The University of Auckland and in collaboration with HortResearch, the Marlborough Wine Research Centre, Lincoln University and winemakers nation-wide, is looking at the effects of growing conditions, fermentation and aging in the bottle on wine aroma.

Normally, winemakers use commercially-available yeast, or Saccharomyces cerevisiae, to cause fermentation of the sugar in grape juice to alcohol and flavour compounds. The University’s yeast research has examined naturally-occurring yeasts at the vineyards of Kumeu River, on the outskirts of Auckland. By testing the yeasts found on the vines and in the juice, scientists have isolated a species of yeast which works together with the S. cerevisiae to produce higher levels of thiols, which are some of the compound which give Sauvignon its fruity taste.

"Kumeu River has a philosophy in winemaking which uses the yeast that occurs naturally on the vines to ferment the grapes," says Dr Matthew Goddard of the School of Biological Sciences. "By working with this very successful vineyard, we have managed to isolate a yeast which adds to New Zealand Sauvignon’s distinctive characteristics. This trial will let us see if the yeast will also work in a commercial setting."

Editor's Note: Original news release can be found here.