It turns out you can acquire that unique Belgian strain used by your favorite brewery, even if there isn't a viable substitute at your local homebrew shop. Commercial breweries rely on yeast just like homebrewers do, and if they are bottle-conditioning their beers, there are likely some living yeast cells in the bottle, just waiting to ferment your next batch of beer.
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Forgoing the precision of modern technology, these cider makers embrace the old-world method of fermenting with yeast already present on the skins of the apples. While producing cider using native fermentation can be unpredictable, the results can offer an array of savory and earthy flavors—these ciders are more complex than any others in the American cider landscape.
If there's one trend in craft beer that has fought hardest to beat out the hoppy-hoppier-hoppiest IPA arms race, it's the boom in popularity of sour beer. These small production, time-intensive brews offer an intriguing history (and hype-inducing rarity), but it's their unique flavor that seems to turn most drinkers into dedicated sour beer fans. The tart, puckering taste is often met with a shocked, love-it-or-hate-it type of reaction, and those with the former can't seem to get enough of the stuff. The secret ingredients that set these beers apart from the rest of the brews on the shelf are actually living creatures: yeast and bacteria.
Folks in the beer industry like to say that brewers don't really make beer. Brewers make wort—which is the stuff that yeast makes into beer. Yeast and its performance has a huge impact on a brewer's final product. But what does that taste like?
Sour ales are one of the biggest things in craft beer right now. The style that started out as a niche Belgian import not too long ago has spread like wildfire across American bars and breweries. Producing sour beer at home can be difficult, but with some experimentation and education there's nothing stopping a homebrewer from creating a tart and funky ale just like the best of the commercial brewers.
Brewers have always reused yeast, though they did not always know it. The German Beer Purity Law, "Reinheitsgebot," from 1516 said that beer could only be made with three ingredients: barley, hops, and water. But German brewers following this law carried over a small portion of each batch to the next, not knowing that this practice transferred the all-important yeast from the old batch to the new. Families in Scandinavia once passed down prized beer-brewing sticks that were used to stir the wort and magically induce fermentation...by introducing yeast to each new batch of beer.
Yeast: The Practical Guide to Beer Fermentation walks us through some of the mystery of brewing, and shows us how we can better use yeast to produce the flavors that we want in our beer.
Prior to the 18th century, yeast was the unknown quantity in beer production. Yeast goes unmentioned in the Reinheitsgebot, the 1516 Bavarian 'beer purity law' that specified only water, hops and barley as 'approved' ingredients for beer. At that point, yeast was simply not a recognized part of the brewing process. Brewers were aware that something 'magical' happened somewhere along the line, turning their watery mixture into a pleasant alcoholic beverage, at least when all went well.
The strain of yeast that a brewer selects—as well as the way the fermentation is carried out—has a direct affect on the sake's aroma and flavor. Knowing a little about yeast can help you pick out flavors in sake, and guide you toward discovering which types of sake suit your palate best.