Yacht Cru Wine Guide
How to spot a faulty wine (video)
I am sure you have encountered a wine that did not seem quite right. Either by your own palate and nose or by having a guest refuse it. There are several types of defects in wine and if you have not learned to spot them they can easily be missed. Since the cork defect is the most widely known, it gets the blame for other defects too. Here are a few of the most common faults and how to spot them.
Depending on which study one reads, between 4-7% of all wines closed with natural cork are corked. This is a fair number of wines and is also the reason why the screw cap and synthetic closure industries are flourishing. A wine can become corked when it has been in contact with a cork that has been infected by a fungus that produces a chemical called 2,4,6-trichloroanisole (TCA). It is this chemical that imparts the nasty nose of a corked wine. It exists in different strengths and while some wines will be clearly corked and have a dirty nose of humid card board, old socks and a hint of chlorine, others might just appear flat and lack any fruit aromas. Once you have learnt to spot it, it is an easy one to recognize.
Please note that a cork defect can not come from bad storage or hot temperatures. It can only be caused by TCA on the cork!
Although oxygen is a very important part in wine making and also during the development of a wine, too much oxygen will result in an oxidised wine.
This can happen if the wine has been left in the fridge standing up for a long time. The cork may harden, which in turn may lead to too much oxygen getting into the bottle. This also the reason wines can’t be kept for too long after opening. An old wine, or an incorrectly stored wine can also be oxidised upon purchase. Hot temperatures, for example, will increase the rate of any chemical reaction of which oxidation is one. An oxidised wine will lack fruit aroma and seem very tired and flat. A white oxidised wine often smells of apple puree and red wines a bit like Madeira. The colour can also be a hint of oxidation. if the colour of a white wine is surprisingly dark it is most likely a sign of oxidation.
This is a defect that perhaps is the most tricky to spot if you are not tasting wine on a regular basis. A “cooked” or “out of condition” wine will smell flat and tired, and lack any vibrant fruit scent. It can be similar in style to oxidation but is much milder. It is the result of bad shipping or storage. It is sometimes difficult to find suitable storage on board yachts and for a couple of weeks this is not a problem but for any longer period the wines may well lose some of their vibrant quality and finesse.