yeast used in winemaking

A frequent customer posed an interesting question earlier today, when she asked for my opinion on the following story in last Saturday’s Montreal Gazette:
It’s a Question of Yeasts
…in case you didn’t follow the link, it’s an article about the growing use of “cultured” yeasts in “winemaking.”

Here’s what the Encyclopeadia Britannica has to say about Saccharomyces:
Genus of yeasts belonging to the family Saccharomycetaceae (phylum Ascomycota, kingdom Fungi). An outstanding characteristic of members of Saccharomyces is their ability to convert sugar into carbon dioxide and alcohol by means of enzymes. The yeasts used to ferment sugars in the manufacture of baked goods, beers, wines, distilled spirits, and industrial alcohols are all strains of one species, S. cerevisiae. One such yeast cell can ferment approximately its own weight of glucose, the simplest form of sugar, in one hour.
(http://www.britannica.com/eb/article-9002436)

One of the many components of terroir, is the particular strain of yeast that thrives in a particular vineyard…which may be different than that in an adjacent vineyard. Terroir is not just about “soil.”

We tend (all things being equal) to prefer naturally produced wines that haven’t been sterilized and inoculated with “cultured” yeast. Granted, if you’re trying to produce industrial quantities of wine, using what are called “indigenous” yeasts isn’t practical – it’s much better to just “nuke” the juice, and introduce a “predictable” yeast.

This is why so many fake wines and garbage “Beaujolais” taste so similar.

Last year while having dinner at Ratcliffe in Charlotte, I ordered a bottle of Pinot Noir from Oregon – from a property whose wines I’d had (and liked!) in the past. It tasted like cherry cough syrup – very woody, cherry cough syrup.

So, I did a little investigating and found that the winery in question did, indeed, sterilize the juice from their beautiful, organically grown fruit, and introduced the following yeast strains: (76%) Assmanhausen, (19%) RC212, (5%) RA17…hmmm…nothin’ says “Burgundy style” quite like ‘em.

Turns out, this is the norm these days. These “cultured” yeasts provide “flavor profiles” that the wine press “likes” (just like kids like sugar), and the resulting wines garner “high ratings.”

Wines that are produced naturally teach us more about wine than manipulated wine “products.” They taste real, and they’re idiosyncratic, and smart people appreciate ‘em – this must be true, because we’ve only got smart customers, and they come back time and again, for the real McCoy.

So, ask me how I really feel about “cultured yeasts” in “winemaking.”

Posted by David Moore