Last issue, we tortured our yeast for science. We flipped our best practices to the dark side and learned the effects of low pitching rates, oxygen starvation, and crazy temperatures. This time, we’re going to follow a similar path, but our goal is to better understand a very common flaw in homebrewing: oxidation.
Over the years, I’ve probably judged hundreds of homebrews that suffered from oxidation that sucked every spark out of the beer. You can start with a great recipe and the finest ingredients and still end up with a glass full of lifeless dreck, sabotaged by poor handling.
Oxygen is the basis of life, but it’s a double-edged blade. Our metabolisms rely on energy driven by oxygen’s ability to react with other chemicals; that’s also why we want to provide yeast with oxygen up front. But yeast cells aren’t too picky about finding a partner, and just as your best tools will rust away in dampness, oxygen can make your beer fall apart into distasteful side-products.