June 18, 2020
If you’ve ever poured an ice-cold craft beer like an IPA into a glass and it looked unfiltered when it was most definitely filtered, your beer might have chill haze.
What Is Chill Haze
Chill haze happens when a beer is chilled below 35°F and polyphenols like tannins, are cross-linked through weak interactions such as hydrogen bonds to create larger particles. These polyphenols come mostly from your grain bill, but they also come from your hops. Often mistaken for yeast, this haze is temporary and doesn’t affect the flavor. Chill haze completely redissolves as the temperature rises and the bonds break up.
Even though chill haze doesn’t affect the flavor, it does affect the shelf-life of the beer. The polyphenols will cause your beer to go stale much faster than regular beers. Hazy beers in general, like the hazy IPA, will go stale sooner than non-hazy beers.
Why Does My Beer Have Chill Haze?
Chill haze occurs with wort oxidation and an insufficient cold break during cooling, in other words not chilling your wort fast enough after the boil and before primary fermentation. Also, poor handling during packaging (aka bottling) can cause permanent haze and permanent off-flavors.
How To Prevent Chill Haze
- Reduce the wort’s exposure to oxygen
- Rapid cold break by using an immersion chiller, counterflow chiller, or a plate chiller
- Adjunct sugars in place of barley as adjuncts have fewer proteins to cause polyphenols
- Lower alpha acid level hops in your first hop edition
- Clarifiers and finings will help polyphenols to drop out
Depending on the style of beer you are brewing, polyphenols can also impart desired flavor characteristics and act as natural antioxidants. The polyphenols can preserve the original taste of the beer, like in wheat beer kits, so their complete removal is not always desirable.