September 22, 2014 by Prost Brewing
Each bier style has a unique flavor profile, as you’ve no doubt discovered from trying the full range of biers available at Prost Brewing. It’s important to point out that a bier’s flavors go far beyond the base ingredients used, and many factors in the overall brewing process influence how a bier tastes. Many flavor compounds in a bier are the result of the type of yeast used for fermentation, the temperature at which a bier ferments, the length of fermentation and lagering period, and other factors. Some flavor compounds are desirable at certain levels in particular bier styles, and others are not. Here’s a look at some of the common flavor compounds and how to identify their taste.
One flavor compound that’s easy to recognize is isoamyl acetate, which is a type of ester produced by the yeast that gives our Weißbier a banana flavor. Also found in many Belgian styles, isoamyl acetate is desirable in Weißbier because it gives the style an enjoyable layer of character and complexity. There’s also ethyl acetate, which contributes a fruity, solventy, or sweet flavor to the bier; and phenethyl acetate, which tastes like roses, honey, or flowers. Certain levels of these flavors are appropriate in styles like Weißbier, but not in many other German bier styles.
A few other common flavor compounds are acetaldehyde, which tastes like green apple peel, latex paint, or a pumpkin, bready flavor; diacetyl, which tastes like butter or butterscotch; and trans-2-nonenal, which gives the bier a papery, cardboard or stale flavor. Like acetates, acetaldehyde and diacetyl are produced during fermentation. Trans-2-nonenal is produced when an older bier starts to break down, usually after months or years of storage.
Obviously, many of these flavors are undesirable in most bier styles, and can be mitigated or eliminated with proper brewing, fermentation and storage methods. Our status as a lager brauhaus dedicated to a long, cold lagering period after fermentation gives us an advantage in making sure unwanted flavor compounds don’t make it into the finished product.