I invite you to join me on a journey to that wonderful Emerald City I like to call the beer aisle.
You may ask, “Will there be wild beers on this journey?”
To which I would say, “Yes and lagers and ales.”
So, let’s link arms and repeat as we walk: Lagers and Wilds and Ales, oh my! Lagers and Wilds and Ales, oh my!
Entering the beer aisle without an understanding of the source of its complexity can be an intimidating experience. We have so many choices in the beer world these days that even a staunch beer-lover might indulge in a bit of nostalgia for the old days when options were limited to a small handful of similar tasting beers. But we should embrace all our beer aisle options; choice and variety are the spice of life-so let’s take a lesson from our Ozian friends and pull back the proverbial curtain to reveal beer’s core elements and see that it’s not so scary after all.
Beer is comprised of four ingredients, malted grain (mostly barley and sometimes wheat), hops, water, and yeast. Skilled brewers can derive an amazing array of different flavors (and colors) from those four ingredients. Our quest to understand this variety will start with the exploration of the fermentation flavors derived primarily from yeast. As you may have guessed, we’ll be discussing yeast in groups categorized as Lagers and Wilds and Ales (oh my).
Yeast are the magic part of beer. While they don’t tell you its color, bitterness, or alcoholic strength, without these microscopic fungus cells, beer (or wine or spirits for that matter) would not exist. They consume sugar, and in doing so produce primarily carbon dioxide and alcohol. They also produce small quantities of other compounds, however, which can have a major impact on the flavors and aromas of beer. The type and magnitude of these compounds are the cause of the primary flavor differences and categories between Lager, Ale and Wild fermented beer. This is why understanding into which category a particular beer falls can help give you a window into what types of flavors to expect.
Ranking the flavor impact of yeast from greatest to least leads us to start with Wild yeast and bacterial strains (included with the Wild category for simplicity sake). These bad boys are the renegades of the beer world and have only recently been invited into American breweries to participate in an intentional way in the beers that reach us as consumers. The bacterial strain primarily responsible for the proliferation of “sour” beers on the shelf and tap at your local retailer is lactobacillus, while the most commonly employed strain(s) of Wild yeast come from the Brettanomyces genus (Brett for short). Our friend Brett doesn’t make beer sour, but he certainly contributes a lot of flavor. Different strains of Brett can contribute quite strong flavors and aromas ranging from fruity like ripe pineapple to pleasantly “funky” characters somewhat incongruously described as barnyard.
While more restrained in flavor contribution than the Wilds, Ale yeast is also capable of contributing significantly to the flavor of a beer. The technical name for this class of yeast is Saccharomyces Cerevisiae and they generally perform best at temperatures of 60F and above. Because of this warmer temperature, they tend to ferment quickly and produce a noticeable fruitiness in the finished beer. Readily available examples would be the banana character in German Hefeweizen and the spicy/fruity aromas common in many Belgian and English ales.
The final category is Lager yeast, technically, Saccharomyces Pastorianus, this class of yeast perform best below 60F. Because of the cooler temperature, they tend to ferment more slowly and produce fewer of the flavor compounds created during Ale and Wild fermentation. The absence of fermentation derived flavors provides a precise expression of the malted grain, hops and water utilized by the brewer. This is why beers fermented with lager yeast are frequently described as clean and crisp.
Keep in mind, yeast derived flavors are but one component of the overall character of a beer. We will cover the contributions of malted grain, hops and maybe even water in future installments. Until then enjoy the journey and know that a lager or ale or wild beer may be light or dark, sweet or bitter, weak or strong in alcohol, but they each can be identified by the nature of their fermentation.
Lagers and Wilds and Ales, oh my!