|
The Story Behind The Story Of Wild Yeast In Winemaking There are groups of winemakers who continually look for techniques that will help them improve wine quality. The “indigenous yeast” trend became a buzz word popularized by influential wine critics of wines made with more natural, less interventionist techniques. Native yeast start the fermentation naturally in contrast to the common Fining (clarification of wine by filtration and chemical additives to precipitate out suspended solids) and filtration are examples of “interventionist” techniques some critics object to, perceived as excessive manipulation which compromises wine quality. This view is contradicted by top
What role should the wine writer have in the winery? Williams believes a limited one: "Wine writers do have a place in the cellar - reflecting on and communicating the vision of the winemaker. To me, the most interesting wines are those made with conviction based on the personal experiences of the winemaker. That conviction can change, that's how wines get better, but it should not shift with the wind." Williams, a long-time user of wild yeast, feels that the inherent risks are overstated. He says, “You bring grapes into a winery and you’re faced with risks. I don’t think those risks are substantially increased by using natural yeast fermentations and that is 20 years experience. I don’t want to say that we’ve never had a fermentation problem that is not true, we have. But I think there may be some benefits to an overall program of using natural yeast that come with it, the wines are more harmonious, more knit and reflect their vineyard character more closely.” Terry Adams, Winemaker at Sonoma-Cutrer Vineyards, comments on the wild yeast trend: “There is a continuum, 10% of the wines I think are excellent and 10% I think should be sold in bulk and there are wines in the middle. I do about 10-15% of the wine that way because I like the complexity. But I like the clean fruit characters that I get from cultured yeast. I continue to work with it because I think it's fun and exciting, but it just doesn’t work for me the way it seems to work with other people. I think it’s a great philosophical approach; I just don’t know that everyone has the same indigenous yeast. We’ve decided which yeast we like and they work well for us.” Most winemakers using wild yeast are looking less at the marketing dividends and more at the potential for enhancing wine quality. Saccharomyces cerevisiae is referred to as the “true” wine yeast, and it’s only on about 1 in 1,000 berries. Its alcohol tolerance enables fermentation up to and beyond 13% alcohol. Also on these grapes are other species of wild yeast, bacteria and mold. Generally, S. cerevisiae is the least prevalent of these microbial species. For the first one to three days of a natural fermentation, the wild yeast predominate. As alcohol levels reaches 3-4%, the wild yeast give way to the increasing numbers of alcohol tolerant Saccharomyces and in two to five days this yeast predominates. At the end of a natural fermentation, usually only S. cerevisiae yeast is present from a multiplicity of strains (as many as 16) in such fermentations. Whereas in inoculated fermentations, S. cerevisiae predominates from beginning to end because of the high level of inoculum. However, some of
Terrific Wine Offerings - CLICK HERE
|
|
followers of wild yeast would prefer an inoculated fermentation, as when rain at harvest washes off the native yeast, reducing their populations. The ensuing rot contains bacteria and mold, which can, during the longer lag phase of native yeast fermentation, proliferate and ruin the wine. The irregularities of natural fermentations require closer monitoring which may be impractical on a large scale. By matching the right grape varieties to the right growing regions, winemakers will be working with high acid, low pH fruit, reducing the risks of wild yeast fermentations.
