Below we have described the most common faults that occur in wine. If you discover one of these faults we recommend that you replace the cork or screwcap and take it back the place where you purchased it. You should get a full refund or at lease a replacement. This particularly applies to restaurants. They recognise that faulty wine is a fact of life and are nearly always happy to replace the wine. If the sommelier recommends that you try a different wine, does so. He is politely trying to tell you one of two things: either he considers the wine to be past its best and a new bottle will make little difference or he thinks is fine and you just do not like it!

 

 

Cork taint is the most common fault associated with wine. As it can only occur when cork is used it is rarest amongst New Zealand wines due to the preference for screwcaps. It is caused by a chemical used in treating the cork which reacts with and spoils the wine. To recognise it you should expect to smell a damp mustiness rather like the mould on old bread. Sometimes the cork taint is more prevalent when the wine is tasted rather than smelt. Opinions differ on how often cork taint appears but the consensus seems to be that it occurs in 3-4% of bottles.

 

 

This is where air has got into the bottle via a faulty seal or where the bottle has been left open for too long. It sometimes occurs where the wine was not correctly protected from exposure to the air when it was made. Whatever the reason, the wine usually has a slightly metallic nose and tastes flat, tired and insipid. Affected white wines also tend to have a rather golden colour. 

 

 

Happens where the sulphur dioxide, used to protect the wine from oxidation during its making, bonds with hydrogen to create hydrogen sulphide. This is immediately apparent when the wine is opened as there will be an unmistakeable aroma of sulphur or rotten eggs. We suggest that you leave the wine for 10 minutes as the smell often dissipates and you are left with a perfectly drinkable and pleasant wine.

 

Tartrate Precipitation 

 

Evident when you get a mass of blackish crystals in the last glass poured from the bottle. It is a result of the wine not being fully stabilised before bottling. It does not affect the taste of the wine and the crystals are harmless. In fact, it can be a sign that the wine was hand made without too many chemicals processes being involved.