Trying to write today's blog post is a bit of a challenge. Quite honestly, today sucked. We talked all day about beer stability and the different ways that beer can go bad. The bulk of the conversation revolved around "Don't expose beer to oxygen."
The day actually started off with an interesting conversation. We touched on how fermentation parameters can effect beer stability. Basically, any secondary yeast metabolites such as esters, fusel alcohols, and aldehydes will age quicker than beers with lower concentrations of by products. We also talked about how filtering can actually make a beer LESS stable (counterintuitive from everything that most of us know about filtered beer) and how bottle conditioned beer can lead to a much greater life shelf as a result of yeast taking in any oxygen that might be dissolved in beer. As you may have guess by now, oxygen is one of the biggest problems that leads to spoiled beer.
As the professor was speaking, I began to realize how recipes, in addition to brewing practices, can effect staling in beer. This was never something I had to worry about as a homebrewer, but now that we bottle at Blue Pants, the oxidizing effects of various ingredients will definitely come into play as we develop future recipes. We also talked about a few simple tests that we can do in the brewery to see how our beer ages. We have already been doing some of this at work, but I look forward to doing these tests with greater effectiveness when I get back.