Subscriber Exclusive

Hunting for Diacetyl

Learn to identify diacetyl in your batches by honing your palate and performing a few simple tests.

Josh Weikert Jul 10, 2016 - 8 min read

Hunting for Diacetyl Primary Image

While there are a myriad of faults that brewers discuss, debate, and diagnose, one of the most common is diacetyl, which is a fermentation by-product found in basically all fermenting (and some fermented) beers. Under normal circumstances, yeast cells are happy to go around and clean up the diacetyl produced while creating ethanol, but sometimes they don’t get to it all (usually through our own mistakes).

Today isn’t about how to avoid diacetyl, but here’s a quick and dirty primer:

1. Select a yeast strain that is less likely to produce diacetyl.
2. Hold the initial fermentation temperature in the lower range for the yeast.
3. Bring the fermentation temperature up a few degrees in the last few days of active fermentation and hold it there for 3–7 days.
4. There. Now you know how to avoid diacetyl (in theory).

Make & Drink Better Beer

Subscribe today to access all of the premium brewing content available (including this article). With thousands of reviews, our subscribers call it "the perfect beer magazine" and "worth every penny." Your subscription is protected by a 100% money back guarantee.