Wine fault
Sediment
Dark deposit in aged red wine, made of tannin and colour compounds that have polymerised and dropped out. Entirely normal.
Yes. Sediment is precipitated colour, tannin and tartrates that were dissolved in the wine when it was young — it is the wine, not something that got into it. It is gritty and bitter if you drink it, which is why bottles are decanted or poured carefully, but there is nothing in it to avoid.
What you notice
Appearance
- Dark, fine, gritty deposit in the bottom of a bottle of red wine
- The last glass from the bottle is cloudy or gritty
What it is
Sediment in an aged red is a sign of maturity, not spoilage. It is the physical evidence of the tannin softening that made the wine pleasant to drink.
It is harmless but unpleasant in the mouth — gritty and bitter — which is the actual reason for decanting older wine.
Finding sediment in a young wine is more likely to mean it was bottled unfiltered, which is a deliberate stylistic choice rather than a problem.
Vintage Port throws a particularly heavy deposit and effectively always needs decanting.
What causes it
- Tannins and anthocyanins bonding into larger molecules over years and becoming insoluble.
- Unfiltered or unfined winemaking, which leaves more material in suspension.
- Vintage Port and traditional-method wines disgorged long ago are particularly prone.
Can I fix it?
Nothing to fix
Nothing to fix. Stand the bottle up, pour carefully, and stop before the deposit reaches the neck.
What you can do
- Stand the bottle upright for a day so the sediment settles.
- Decant slowly and stop when the sediment reaches the neck.
- A light shone through the shoulder of the bottle makes it easy to see coming.
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.
- Shaking the bottle to mix it back in
- Puts gritty, bitter material into every glass instead of the last one. The opposite of what you want.
Is it safe to drink?
Not a safety problem
Unpleasant, not harmful. You can drink it; you may not want to.
Yes. Sediment is precipitated colour, tannin and tartrates that were dissolved in the wine when it was young — it is the wine, not something that got into it. It is gritty and bitter if you drink it, which is why bottles are decanted or poured carefully, but there is nothing in it to avoid.
Can I take it back?
No. In an aged red this is expected and normal.
Sources
Sources consulted
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