Fault
Chill haze
A temperature-dependent haze from protein and polyphenol binding — cosmetic only, and by definition it clears as the beer warms.
Also called cloudy beer, hazy beer, cloudy, why is my beer cloudy.
What it looks like
Straight from the fridge
Proteins and polyphenols bind loosely as the beer chills and come out of solution as particles large enough to scatter light. Nothing has gone wrong with the beer; it is a temperature effect.
The same beer, warmed
The bonds break again as the beer warms and the particles redissolve. If the cloudiness clears, it was chill haze. If it does not, look for infection or for yeast in suspension instead.
What it tastes and smells like
Proteins and polyphenols form loose complexes at low temperature and dissociate as the beer warms. That reversibility is the diagnostic: if the haze disappears as the glass warms, it is chill haze. If it does not, it is permanent haze, an infection, or a deliberately hazy style.
It has no effect on flavour and matters only where the style is meant to be brilliant.
Where it may be expected
Several styles are deliberately hazy, and in a New England IPA the haze is engineered from protein, polyphenol and low-flocculating yeast. Chill haze is only a fault where the style calls for brilliant clarity.
Intensity and context decide. In the styles below a restrained version of this can be part of the character; the same character running past that is still a fault there.
Styles this tends to affect
Not where it belongs — where it is most likely to appear when something has gone wrong.
- American wheat beer — A wheat beer fermented with clean American yeast: soft body and lasting head, without the banana and clove.
- Kristallweizen — A filtered Weissbier: the same banana-and-clove character in a brilliantly clear beer with a lighter, crisper body.
- New England IPA — Hazy, soft and intensely aromatic: tropical and stone fruit hop character with deliberately low bitterness and a full, juicy body.
- White IPA — A hybrid of witbier and IPA: wheat and Belgian yeast spice underneath American hop aroma.
- Witbier — A Belgian wheat beer brewed with unmalted wheat, coriander and orange peel — soft, hazy, citrusy and lightly spiced.
If you are drinking it
Haze that clears as the beer warms is harmless and affects nothing but appearance. Haze that stays, or that comes with unexpected sourness, is a different matter.
Not a safety issue. Beer’s alcohol, hop compounds and low pH make it inhospitable to organisms that cause illness.
What causes it
| Cause | Stage | How often | Who can act |
|---|---|---|---|
| Protein and polyphenol complexes forming below about 5 °C and redissolving as the beer warms. | conditioning | most common | brewer |
| Not holding the beer cold for long enough before filtering or packaging for the complexes to drop out. | conditioning | common | brewer |
If you are brewing it
- Brewer: Cold-condition below the intended serving temperature for long enough that the complexes drop out, and use a vigorous boil with a kettle fining for good hot break. (prevents)
Where in the process this comes from
Steps that can produce this fault when they go wrong. Each links to what the step is for and how it is controlled.
- Cold crashing — Chill finished beer sharply to near freezing to force yeast and haze-forming material out of suspension before packaging.
- Conditioning — Mature beer after primary fermentation so flavours settle, harsh young compounds are cleared and carbonation reaches equilibrium.
- Lagering — Store beer cold for an extended period after fermentation to clarify it and produce the clean, rounded character lagers are named for.
- The boil — Boil the wort to isomerise hop acids, sterilise it, coagulate protein, drive off unwanted volatiles and concentrate the extract to the target gravity.
- Wort chilling — Cool boiled wort rapidly to pitching temperature, producing a good cold break and passing quickly through the range in which spoilage organisms thrive.
Often confused with
- Permanent haze — cloudy at any temperature, persistent cloudiness that does not clear
- Infection — unexpected sourness, barnyard
Evidence
What BeerHQ knows about this, and how. Every statement carries the state of the evidence behind it rather than being presented flatly as fact.
Chill haze consists of complexes between proline-rich proteins and polyphenols that come out of solution when beer is chilled and redissolve as it warms, which is what distinguishes it from permanent haze.
Backed by a source
Sources: Brewing: Science and Practice — print; Beer: Tap into the Art and Science of Brewing — print