Economy Size Geek

A Skunk Walks into a Bar . . .: Science News Online, Dec. 3, 2005

Props to Droth for forwarding this along.

Couple of notes about the article:

1. The hop additions can be a little more complicated than described since you can add a bittering hop, flavor hop, aroma hop, and dry hop. The distinction is when you add it to the process. Bittering hops are added at the begining of the boil while flavor and aroma hops are added at the very end (much like adding spices to a stew). Dry hops are added during fermentation.

2. Although all beer does go bad eventually - there are certain styles which are prized as they get older. Thomas Hardy barley wine can apparently be aged up to 30 years. Most of the high alchol belgians can be kept for up to 5 years. And a lot of your Christmas Ales can easily be kept a year or more. There is no doubt that the flavor changes during this process. In many cases the over powering hops and other spices that are so dominant in fresh brew “roll off” - allowing you to taste a much more complicated beer underneath.

We just did a vertical tasting of Stil Nacht from Du Dulles (Beligum) with a 2004,2003, and 2002. The 2003 ended up being my favorite - mostly because it was less assertive and pungant than the 2004, but more full bodied than the 2002.

Since there are much fewer guidelines for how long to age the beer it is a dicey business. I’m currently following the system of trying to put away a number of bottles and then opening them on a 6 month or so cycle. Hopefully that way I can get them at the peak or just behind th peek before they go bad. Which is pretty much the worst thing that can happen to a beer that you’ve been holding on to.

3. They are right on about the obsession about oxygenation. At every turn the guide books warn you about keeping it to a minimum. I didn’t think about how quickly it would be absorbed into the liquid itself. I was usually looking at the gap at the top of the fermenter when I was thinking about the oxygen. On the other hand you are a little caught because when you brew the wort in the first place you boil out all the oxygen and the yeast apparently needs it to get down to business. So before you add yeast you end up putting a lot of oxygen into the wort. Once you add the yeast the rest of the time is spent trying to avoid letting any O2 in.

4. The creation of furfuyl alcohol was one of the most interesting things to me. Since it seems to be triggered by a long very hot boil. This is somewhat counter to everything I’ve learned so far. I have always been told that you wanted a very hot boil to make sure that certain compounds that could build up other wise and will ruin both the taste and look of the beer would be there. So now I want to do an experiment where I do two batches with different boil temps just to see how much of an effect it has.