WHY SOUR?
THE ART BEHIND TART & BARREL-AGED ALES
1. BREWING
Making wort for a sour beer can be considered much the same as brewing any other beer; the brewer is just playing more of a “long game” when making a sour. We will try to maximize the amount of sugar that is not fermentable by typical brewer’s yeast as a means of providing food for the “bugs” we later introduce, which have the ability to break down these non-fermentable sugars. The more fuel left in the beer for the yeasts and bacteria we introduce, the more profound their impact on the finished product.
2. FERMENTATION
There are an infinite number of combinations a brewer can utilize in sour brewing. The basis of all of these can be summarized as containing one or all of the following: Saccharomyces (Brewer’s Yeast), Brettanomyces (Wild Yeasts), Lactobacillus and Pediococcus (acid-producing bacteria), or Spontaneous (typically a combination of some or all of these naturally occurring flora, which are allowed to inoculate an open vessel). Some sour beers begin their life as a regular Sacch fermented beer and then move on to be inoculated with one or a combination of the previously mentioned “bugs”, others are given wild yeasts and/or bacteria as a primary fermentor, others still may have been allowed to sour “hot-side” and then the fermentation is completed by a sacch strain.
3. CONDITIONING
Truly just a continuation of the fermentation, again, there are infinite combinations of how the real “souring” phase can be achieved. This is typically the longest part of a sour beer’s life and can take anywhere from a few months to a few years. Depending on the end goal, this phase may take place in a stainless steel vessel, an oak vat, or repurposed oak barrels from the wine and spirit industries. Oak offers a few benefits in that your “bugs” can actually inhabit the cracks and crevices of the wood, as well as those pores in the wood itself, allowing for micro-oxygenation, which generates and alters different flavor compounds. If those characteristics aren’t desired, stainless can offer a more consistent and repeatable medium for sour beer aging.
4. PACKAGING
Sour beers in particular benefit from a high carbonation rate. This can be achieved through modern forced carbonation techniques, but it tends to alter the profile of the beer itself more so than the traditional method of bottle refermentation. The perception of a beer that is naturally carbonated in the latter tradition will give a smoother or less sharp carbonation feel. It lends a finer bubble and creamier texture that doesn’t stand out against the strikingly nuanced flavors of the world of sour beer.
GLOSSARY
Wort: The liquid extracted from the mashing process during brewing. Wort contains the sugars that will be fermented by the brewing yeast to produce alcohol.