Wine fault
Protein haze
A soft haze in white wine caused by unstable proteins, usually triggered by warmth.
Yes. Protein haze is grape protein that has come out of solution — ordinary food protein that was in the wine all along, made visible by warmth. It affects clarity and nothing else, and the wine tastes exactly as it would have done clear.
What you notice
Appearance
- A soft, even haze in a white wine, often appearing as it warms — also seen in Haze and cloudiness
What it is
Harmless and cosmetic. Producers usually prevent it with bentonite fining, though that process can strip some aroma, so there is a genuine trade-off.
It is distinguishable from other haze by being even and soft rather than particulate, and by appearing when a bottle warms up.
What causes it
- Naturally occurring grape proteins becoming unstable and clumping together, typically when the wine warms.
- Insufficient bentonite fining before bottling.
Can I fix it?
Nothing to fix
Nothing to fix. It is dissolved protein made visible by warmth, and it is harmless.
What you can do
- Nothing. Chill it and drink it.
What does not work
Published because a reader holding a spoiled bottle has usually already been told to try one of these. Correcting the specific wrong advice is more use than stating the right answer beside it in silence.
- Filtering it
- Would remove the haze and some of the wine’s texture with it. It is a cosmetic issue and not worth the trouble.
Is it safe to drink?
Not a safety problem
Unpleasant, not harmful. You can drink it; you may not want to.
Yes. Protein haze is grape protein that has come out of solution — ordinary food protein that was in the wine all along, made visible by warmth. It affects clarity and nothing else, and the wine tastes exactly as it would have done clear.
Can I take it back?
No, unless the wine also tastes wrong.
Sources
Sources consulted
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