A little wildness in the cellar, eh? Very apropos as we’re well into the 2012 harvest, by now, and tanks and barrels are busily bubbling away as we speak.
In a recent post I managed to record a one-minute description of how wine is made – whew! In that post I mentioned that wine was probably discovered by accident because yeast is everywhere, just like bacteria. And, all you need to make wine is grape juice and yeast. Wild yeast strains come in with the grapes and often take up residence in the winery.
The vast majority of wine is made by inoculating the juice or must (crushed grapes) with cultured wine yeast. It’s the best way to make sure the job gets done and, these days, also because the winemaker can select a specific yeast that brings out the black currant character in Cabernet or the floral nature of Muscat. They can select heat and cold tolerant strains, low-foam strains, yeast that tolerates high alcohol…
But in fine wine production, some winemakers choose to go native – they let nature take its course rather than adding wine yeast. It’s a calculated risk. Since the winemaker doesn’t know what kind of yeast is at work, or how much of it is present there’s a chance that he’ll have a “stuck fermentation” which means the yeast has petered out before the job is done, leaving him with a tank of sweet Cabernet – yum! Continue reading