Most beers are brewed using a strain of the Saccharomyces genus of yeast, which has been selected over time to provide a specific flavor profile. Ale yeasts typically belong to the species Saccharomyces cerevisiae. They form a thick layer of foam on top of the wort during fermentation, work at a relatively warm temperature of 60-70 degrees Fahrenheit and finish quickly. Lager yeasts generally belong to the species Saccharomyces pastorianus. They ferment much more slowly below 60 degrees Fahrenheit but finish with a drier, cleaner product.
There is a small subset of beers that actually have a sour taste. These beers typically use either a specialized yeast from the same family, Saccharomycetacae, but a different genus, Brettanomyces; or a type of bacteria to achieve the sour taste. The bacteria used are typically either Lactobacillus or Pediococcus, the former of which will produce lactic acid. Both Brettanomyces and the bacteria slowly ferment sugars that Saccharomyces will not, resulting in a beer that continues to mature in the bottle and can become quite dry with age.
The beer this week is Monk’s Cafe Flemish Sour Ale, contract brewed for Monk’s Cafe downtown by Brouwerij Van Steenberge in Belgium. This beer is a Flanders Oud Bruin, or brown ale. These beers are typically a very malty, complex character, which can be almost wine-like because of some tannins. These beers are often blended with fruit juice to create fruit lambics or with younger beers to balance the flavor profile. This beer should be served in a tulip or wine glass and will pair well with red meats, earthy cheeses and dark chocolate.
The beer poured a very, very dark red, to the point that it appeared brown unless held up to the light. A finger and a half of fine foam with a pillowy Belgian texture formed the head, which was a fairly dark tan color. The head dissipated over the course of about five minutes, with very little long-term lacing. The initial aroma had just a hint of dark malts, both roasted and melanoidin heavy, before the main sweet-and-sour aroma hit. Overall it was very complex and tended toward the dark end. The mouthfeel was very smooth overall, with quite low carbonation, almost still in fact. A thickness lasted for a while but dispersed before it became annoying. Overall the mouthfeel was fairly thin with a very light, sweet syrup character. For some reason, this made me think of Troeg’s nugget nectar. The taste started with a sour hit up front, but it quickly flipped to a high, sweet character. Some tart apple taste gave this beer a lot of depth, which was very complex when combined with the overall sweet flavor and the nice, light, sweet finish.
This beer was fantastic — very balanced, with a sweetness and low-level sour that makes it the perfect introduction to sour beers. I can’t recommend this enough, especially for those people who “don’t like sour beers.”