Yeasties and Oddities
Beyond the basics of malt and hops, artisanal brewers take advantage of countless other sources of flavor and aroma when they formulate their beers. Besides water, we are still missing one crucial beer ingredient: yeast. During fermentation, yeast not only turns maltose (sugar) into alcohol, it can provide a full range of flavors. While American strains are usually more neutral, English yeast strains provide fruity esters, German hefeweizen yeast can add banana and clove flavors, and Belgian strains can offer phenolic notes, and wild yeasts can add anything between lemons and horse blankets.
The variety of yeasts is vast, but what does this mean in terms of keeping our beer fresh? The yeast profile of a beer should be regarded similarly to malt flavors of a beer. The overall complexity of a beer can generally be correlated successfully to the shelf life of a beer (with notable exceptions—never forget the hops). Flavors and aromas created by the yeast will fade over time, but the more there is the longer it will take to fade away. Yeast strains that add intense flavors to beers, such as Belgian ale yeast strains, add to the shelf life of beer. Neutral yeast strains, such as American ale yeast, add very little, and so the beer is only as vulnerable to degradation as the sum of its other ingredients.
One oddity when it comes to the age of beer is sour beer, or wild ales and lambics. In these beers, a spectrum of wild yeasts and bacterias help to ferment them, resulting in pungent flavors, mostly sour and funk. Many regard these sour beers as the best beers to age, even though they may have little alcohol and very few hops. While your experiences may vary, these can normally easily be stored for at least a couple of years without any negative impact on the beer.
In my experience, true spontaneously fermented beer, or lambic, from Belgium has better shelf life compared to wild ales brewed in the United States. While collectors would not hesitate to store a lambic for five or ten years, fewer would store an American Wild Ale for more than a few years. I have even seen people drinking a German Berliner Weisse brewed thirty-five years ago that everyone agreed tasted as fresh as any. They keyword when it comes to wild beers is wild… each beer is unique.
After yeast, brewers can infuse any number of miscellaneous ingredients into the brewing process. I’m talking about fruit beers, pumpkin beers, chocolate beers, every kind of beer imaginable is possible. Hell, yesterday I was drinking a mango IPA called Masala Mama from Town Hall Brewery in Minneapolis. In general, added flavorings fade quickly. Not as quickly as hops, but faster than malt. This means fruits, vegetables, chocolate, coffee, and whatever else a brewer can think of will generally fade over time at a faster than normal pace. See the previous Extol Beer article on the necessity of drinking coffee beers fresh for one detailed example.
There are two major exceptions to the fast fading of flavoring rule that stand out. Spices and smoke. Spices mellow relatively slowly over time, but can also act as a preservative in beer. As a result, spiced ales can be quite eligible for cellar aging. Breweries that release spiced holiday ales often turn into collectibles, such as the yearly release of Anchor Our Special Ale or Goose Island Christmas Ale. Smoke beer, or rauchbier, includes malts that are infused with wood smoke. This not only adds obvious flavor and aroma to beer, it acts as a preservative. Beers such as Alaskan Smoked Porter develop in the bottle nicely for a decade.
Now, with an established understanding of beer degradation over time, there is only one thing left to discuss: cellaring.