After blowing up my wine, followed by breakfast, I go to the fridge. Inside, the remaining half-gallon of vignoles juice awaits me. I need to top off the carboy again, now that the carpet is wearing wine. But then…

This is why everything in your fridge is pasturized.

If you find bottles that mention wild, indigenous, or naturally occurring yeasts, or natural fermentation, this is what they are talking about.

Wild yeasts live nearly everywhere from between your toes to the deep sea. Humans and animals first discovered wine thanks to wild yeasts thriving on grape skins and vines. When the grapes were stored or even collected, the skins broke, and wild unseen microbes devoured the sugars. The fizzing and alcohol that resulted seemed magical becoming a part of rituals, offerings and civilization’s second great discovery: drunkenness.

Unlike laboratory-isolated yeasts, the wild ones can ferment erratically. Up to 16 strains vie for supremacy in the pursuit of sugar and oxygen. Without a steroidal lab yeast to dominate affairs, the mix of natural yeasts creates not only unpredictable alcohol levels, but varying flavor compounds, acidities, sulfides and other bi-products based on each strain’s survival throughout the fermentation process.

Since wine-making is expensive, producers usually want reliable returns on their investment. Nothing should spoil, tanks need to ferment fast and easily to be ready the next batch, and the wine should taste similar to last year’s. Laboratory-isolated yeasts ensure quick, consistent results.

Wild yeasts can take a week to start because their populations start small: with one in a thousand grapes carrying any traceable yeast. Once waiting for them to propagate, ten to twenty percent of a harvest can be lost to spoilage. The final range of flavors is more variable, with natural selection running the show.

Yet with the rise of organic agriculture, natural fermentation has become fashionable: like owning a Prius or driving a hybrid purse dog. Brands that have differentiated themselves with the buzzword include, Kistler, Ridge, Tenscher, Sterling, Frog’s Leap etc. While old world producers -by ignoring the tide of trends- have gained notice for already using wild yeasts.

Thanks to native yeast branding, wines can claim to express their place of origin (terroir) more literally than the big brands. This means more variation from site to site and year to year. Greater complexity is possible, as are higher prices. Some consumers will pay out of curiosity, most won’t, for fear of disappointing their expectations. They want Coca-Cola-level consistency from wine not confusion.

Be mindful that naturally fermented wine is not healthier for you. The yeasts are the same. Laboratories have merely isolated and propagated one for its results. But search out the risk-takers and keep an open mind.

In the end, I decide to not add the half-gallon. Adding fresh juice might start a new fermentation that needs to stop. I will see where the wild ones go and let my science project take its own course.

Check out:

Jordan P. Ross

This interesting, detailed, albeit rambling, e-mail interview with Paul Draper of Ridge.