I went to go check on my beer today, and I noticed something interesting. The bubbles coming out of the airlock smelled extremely strongly of bananas. Now, this is pretty normal, but I thought I'd take the time to explain WHY it smells like bananas.
You may have heard of beer tasting or smelling like bananas before. This happens because the yeast, when fermenting, produces phenols that get in the beer. This is not altogether an undesirable trait, and in some styles, this is even a critical part of the beer! In Brew Your Own Magazine, Jamil Zainasheff (a prolific beer writer, homebrewer, and recent founder of a new brewery called Heretic Brewing) wrote a style profile for the German Hefeweizen. In it, he discussed the banana/clove taste that is consistent with the style. He said "The aroma of a good hefeweizen includes moderate spicy clove notes and fruity banana esters." This is definitely what comes to mind when I think of a Hefeweizen (one of my favorite beer styles, for what it's worth). He does caution though, "However, one of the most common mistakes in homebrewed weizen-style beers is having too much clove and banana character. Brewers might point to the BJCP [Beer Judge Certification Program] style guide which says these phenolic and ester compounds can range up to 'strong,' but do not think for a minute that it means a clove/banana bomb is acceptable." So, am I worried that I'm going to have too much banana flavor in my new Super-Secret-Surprise Beer? Well, yes and no.
I'll start off by saying that this newest beer is not a Hefeweizen. So, these phenolic characters aren't really what I want for this style of beer. There can be that hint of banana, but it's not really normal, especially not in any large amounts. That being said, I feel like I'm probably reading too much into the sniffing of the airlock. Every other time that I've brewed, the airlock has emitted some interesting smells that didn't end up in the final product. Also, even though it isn't traditional for this style of beer, I think that the banana flavor here would meld well. So, I'm not too worried about it.
I am wondering, though, why it's so strong this time compared to last time? After doing a little research, I think I know why. First, this is a new style of yeast that I've never used before. Different styles of yeast have different characters, and some smell more like bananas than others. But, more than just that, I think it's my fermentation temperature. Up until now I really haven't had to worry that much about controlling the fermentation temp. The combination of a cool apartment and tame yeast have allowed the temperatures to keep fairly low by themselves. Now, however, the ambient temperature in the apartment has risen, thus raising the original temperature of the beer. Also, this beer, as mentioned before, has been fermenting like crazy. At one point the fermenter even got up to 73 degrees. THIS, I believe is the main culprit with the banana aroma.
In the future, I will probably try to control the fermentation a little better. I can do this through a few different ways, but the easiest seems to be something called a Swamp Cooler. For now, though, I don't think I'll be able to do that, just because money is tight.
Anyway, I hope you enjoyed learning a little more about what makes your beer B-A-N-A-N-A-S!
No comments:
Post a Comment