"Can you check this wine please? I think there's a problem with it."
This is a common request in restaurants and one that staff feel out of their depth trying to answer. Wine is not a perfect product and it often comes with faults. But how do you spot them and which ones mean that the wine needs replacing? Here are 4 of the most common faults and the things to look out for.
1. Cork Taint
This is granddaddy of all wine faults. It’s caused by a mould that infects the cork, and this then infects the wine. The unwanted fungus creates a chemical known as TCA (2,4,6-Trichloroanisole) which will make the wine smell and taste quite nasty. If you love the aroma of mouldy wet carpets, wet dogs or an old gym bag, then you’ll love this fault. But most people won't be happy with what's in their glass. Don’t stress. It’s not your wrongdoing. Around 5% of wines sealed with a cork have this problem. Your wine supplier will be happy to give you a new one, at no cost, so just open another bottle and everyone will be happy.
2. Oxidised Wine
As the name suggests, this is a wine where oxygen has affected the quality of the wine. Wine actually needs a little oxygen to help it develop and certain wines (Sherry, Maderia) use oxygen exposure to create their own unique style. But if a wine was meant to be fresh and clean and it gets too much O2 exposure, it can completely ruin the wine. It might be an issue with a cork that failed to seal properly, or poor wine making standards may be to blame. What you’ll notice is a tired, dull wine. It may have started to turn brown or even orange in colour. If it does smell nutty and rancid, you need to replace the bottle, and hope there’s not a repeat performance with the next one.
3. Heat Damage
Also known as ‘cooked wine’, this is a problem with how and where the wine has been stored. Most white and red wine like a cellar temperature somewhere between 10-18⁰C. If they go too far above this, they can start to change chemically inside. You might see the cork starting to push out the end of the bottle. This is always a giveaway sign. The wine may also be oxidised, so you can expect it to smell and taste stale with dried fruit and Sherry-like flavours. Replace the wine for the guest and take a serious look at your current wine cellar conditions.
Delicate bubbles dancing about in your favourite Champagne are to be expected. But if they start showing up in a full-bodied red wine, then you know you have a problem. Refermentation occurs when a wine is bottled with small amounts of sugar and yeast still present. If not stabilised properly, they can kick off the fermentation again, trapping tiny carbon dioxide bubbles inside. The wine may be described as lightly ‘spritzy’ or ‘fizzy’. You could give the bottle a good shake, to get rid of some of the problem, put this is not a good look during service, so just open a fresh bottle.