May 21, 2015 by fhsteinbart
Not too long ago I got to participate in a blind tasting which involved a triangle test with two beers that were exactly the same except for one major difference. One beer had been dosed with artificial butter flavor and the other had not. This was meant to model the normal beer vs. one with diacetyl. While this evaluation was not totally objective as we knew one of the beers had been dosed with diacetyl, it brought home the need for objective assessment in analyzing off flavors as found in defective beers. After a great deal of research I came up with a list of over three dozen different types of off flavors that are found in defective beers. While this list is not entirely comprehensive I discovered that you can go to the local supermarket and find most of these items for a reasonable price as compared to actual Sensorineural off flavor kits. While you can buy these kits for around $200, you can actually save a great deal of money by simply shopping wisely at your local market. As an example, acetaldehyde, has a green apple flavor like that found in germinating barley or in some American light lagers. Another very common off flavor found in beer is DMS or dimethyl sulfide which has a creamed corn or canned vegetable flavor and aroma. Probably the most important off flavor as it relates to beer, is diacetyl, which has a buttery or butterscotch flavor. If you would like to doctor a beer such as a light American lager, you can use canned creamed corn or black olives to imitate the off flavor of DMS. Also, you can use McCormick’s imitation butter flavor to illustrate the flavor of diacetyl in a light American lager beer. Acetaldehyde can be best illustrated by using either green apple juice or germinating barley to imitate the flavor of a beer contaminated by acetaldehyde. Next week we will be discussing the less common but still prevalent off flavors as found in beers which did not ferment correctly. So until then, cheers and hoppy brewing!