When it comes to flavoring beer, it seems that hops and grains get all the love. Yeast gets least—and that’s just not right.
Yeast is beer’s flavor-pumping heart. These hungry fungi convert grain-derived sugars into carbon dioxide and alcohol—hard work marked by fragrant by-products. Yeast can contribute more than 600 flavor and aroma compounds to beer (though most lurk at levels beneath olfactory detection). They’re both positive and negative, and include cloves, apples, bananas, sulfur, butter and more.
No two strains are identical, and the beer yeasts split into two major families. Ale yeasts favor warmer temperatures, supplying fruity verve to styles such as stouts, barley wines and IPAs. Slower-working lager yeasts (lagern means “to rest” in German) savor cooler climes to create styles such as brisk Pilsners, warming doppelbocks and Mexican beach crushers. Both yeasts cease eating the sugars when full. Don’t stress them (ideal temperature, enough oxygen) and they’ll replicate flavors consistently.
Then there’s the black sheep: Brettanomyces. This unruly yeast (read: wild) feasts till the cupboard is bare, drying out beer and lending funky, shape-shifting notes of earth, barnyard and hay, sometimes adding tropical fruit and tartness.
With so many commercial yeasts, why are brewers increasingly turning to wild strains, spontaneously fermenting beer or hunting down distinct fungi? In today’s competitive market, unique yeast strains often yield interesting, complex and different aromas and flavors that can make a beer stand out and provide an unforgettable drinking experience. From classics to modern curiosities, these five beers will help you bug out.
Made by Belgian monks, this ale has an easy-drinking appeal that contradicts its 9.5% abv. A heavenly mix of cracked pepper, cloves, ripe pears and apples, this tripel showcases the distinctive traits of its Belgian yeast strains.
This Pittsburgh brewery ferments its idiosyncratic, European-influenced elixirs with locally harvested yeast. Hazy gold Relic, made with microbes isolated from a 17th-century cabinet, is a funky mélange of citrus and earth.
Wheat gives this smooth and elegant German beer its lustrous head and hazy hue. Its distinct lager yeast—not spices or fruit—supplies the trademark clove-like aroma and appetizing banana flavor.
Spontaneously fermented with Maine microflora, Coolship Resurgam is a fusion of beers, each aged in French oak for one to three years. It’s bright with lemon notes, and it’s engagingly acidic, with a dry, tannic finish.
An Oregon saison that’s first fermented with four yeast strains, weaving a tapestry of citrus, tropical fruit and pepper. The later addition of wild Brettanomyces yeast imbues baseline funk.