Fault or false alarm? How to tell if a bottle of wine is genuinely off

You open a bottle, give it a sniff, and something seems wrong. Before you tip it down the sink or march it back to the shop, it is worth running a few checks. Wine can be genuinely faulty, but it can also be too cold, too warm, struck by a passing smell in the kitchen, or simply closed and in need of air. Learning to tell the difference saves money, saves good wine and makes returning a bad bottle much less awkward.

First, rule out the obvious

Temperature is the most common false alarm. A white straight from the fridge can smell of almost nothing; the cold mutes the aromas and makes the acidity feel sharp. Let the glass warm in your hands for ten minutes and smell again. A red served too warm — near a radiator or in a hot kitchen — can smell boozy and flat. Give it a few minutes to cool.

Air is the second false alarm. Some young wines are “closed” or “shy” when first opened. They may show a little struck-match or rubbery note from reduction, especially in styles such as Syrah, Riesling or some natural wines. Swirl the glass, pour a small amount into a jug, or decant the bottle for 20 to 30 minutes. If the fruit starts to emerge and the odd smell blows off, the wine is not faulty. It was just holding its breath.

The four faults you can spot at home

Cork taint

Cork taint, usually caused by TCA, smells of wet cardboard, damp basement or musty newspaper. The fruit seems stripped away, and the wine can taste dull and bitter. It does not always shout. Sometimes it is a faint background hum that makes you wonder why the wine is not showing more. TCA does not blow off with air. If the smell stays after ten minutes and a good swirl, treat it as faulty.

Heat damage

A cooked wine smells stewed, jammy or like Madeira, even if it is meant to be fresh and fruity. The cork may be pushed up, the capsule may look sticky, or the bottle may have leaked. This often happens after a hot delivery van, a sunny windowsill or a bottle stored next to a radiator. It is not fixable. Return it if you can.

Oxidation

Oxidised white wine smells of bruised apple, sherry or vinegar; oxidised red can smell tired and nutty. Some wines are made in an oxidative style on purpose, but if a fresh young white tastes like dry sherry, something has gone wrong. A small amount of air can improve a wine; too much over time makes it old before its time.

Refermentation

If a still wine is slightly fizzy, cloudy or smells of yeast, it may have refermented in the bottle. A light spritz can sometimes be a winemaking choice, but a cloudy, fizzy red or white with a yeastiness that grows in the glass is usually a fault. Return it.

The 60-second sensory check

Pour a small measure into a clean glass. Look at the colour: is it clear, or unusually brown for its age? Swirl and smell. Do you get fruit, or wet cardboard, vinegar or stewed fruit? Taste a tiny sip. Is the fruit clean, or does it taste dull and bitter? Wait a few minutes and smell again. If you have a second bottle of the same wine, compare them. That is the quickest way to spot a fault, though it does use two bottles.

Do not judge by the cork alone. A cork can smell musty without the wine being tainted, and a clean cork does not guarantee a clean wine. Your nose and palate are the real test.

What to do next

If the wine is genuinely faulty, keep the bottle, the cork and your receipt or order number. Take a photo of the label and the fill level. Contact the retailer promptly. Under the Consumer Rights Act 2015, goods must be of satisfactory quality, and a corked or heat-damaged bottle is not. Most supermarkets and independent merchants will refund or replace a faulty bottle, though policies vary.

For an online merchant, email customer service with your order number and a short description. They may ask you to return the bottle or send a photo. Do not pour the whole thing away before you have spoken to them. For an independent shop, ring ahead and explain the problem. They may want to taste it, and a calm, specific description — “it smells of wet cardboard” rather than “it tastes funny” — helps everyone.

If the wine is merely closed, too cold or not to your taste, that is not a fault. Give it air, let it warm up, or cook with it. A faulty bottle is a different matter: you paid for a sound bottle of wine, and you are entitled to one.