How to tell if you should send back the bottle.

Is my wine bad?
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Every day it seems like I hear about a new wine fault. So in order not to fall behind, I went on a training day put on by CSWWC (|Champagne and Sparkling Wine Championships) and Plumpton College (like UC Davis but smaller and a lot more English.) I was surprised by the sheer number of things that can go wrong at every stage of the winemaking process from fermentation to bottling and even after. I am sure most readers will know about a corked wine (if not definitely read on) but what about light struck? And what the hell is goût de souris? Stick your nose into a glass and you might find baby sick, mold or even rotting flesh aromas.

Here, just some of the problems you ought to be able to identify with your wine so that you can impress your friends or thoroughly ruin dinner parties. Just to confuse matters, things that some people might think of as a fault can actually be considered an intrinsic part of particular wines. It’s enough to make you turn to hard liquor.

1. Brettanomyces aka Brett

The most common descriptor for brett is sweaty saddles, but as so few of us go around sniffing saddles these days wet dog might be a better sense memory. You might also get barnyard aromas or even old socks! It’s caused by a yeast called Brettanomyces. It normally comes from infected barrels but according to Tom Stevenson from the CSWWC, it can also lurk in the vineyard. He estimated that nearly 2/3 of French wine has some. The funny thing about Brett is that in small quantities, it’s quite nice adding a savory quality—it crops up in some prestigious reds from the Rhone and, though less than before, in Bordeaux.

2. Volatile Acidity

Usually this comes from acetic acid, in other words vinegar. Most wines will have a tiny bit but if you can smell vinegar then there’s probably some sort of bacterial infection. Certain wines such as Château Musar from the Lebanon, old-fashioned rioja, and some Australian shiraz including the greatest of all, Penfold’s Grange, have high levels of volatile acidity. But you shouldn’t be getting it in an everyday red or white. Other volatile acids you don’t want include lactic acid which smells like baby sick. Lovely!

3. Oxidation

This means oxygen has gotten into the wine. Characteristic smells are cider (I’m talking farmhouse hard cider), nuts or sherry. Certain wines owe their character to controlled oxidation such as madeira, tawny port, amontillado and oloroso sherry. Then there are certain wines that flirt with oxidation such as certain Chenin Blancs from the Loire or Marc Sorrel’s famous Hermitage Blanc. But most everyday wine should not have oxidative notes. One good rule: If you’re drinking wine by the glass and it smells raisiny then the bottle may have been open to long.

4. Reduction

If you get a burnt smell, it could be that your wine is reduced. Reduction is the opposite of oxidation; it’s caused by a lack of oxygen. Other smells that point to this include sulphur, garlic, struck match or rubber. Some varieties, especially syrah, are particularly prone to it and you are more likely to get it from screw caps than natural corks because they provide a less permeable seal. A lot of reductive smells will dissipate after time in the glass but if it smells like Hades then you might want to complain.

5. Lightstruck

This is my new favorite one. Tom Stevenson gave us a champagne which smelled strongly of burnt cabbage. At its worst it can smell of rotting flesh.This is caused by the action of light on the wine. It can even happen in the glass if the sun is hot enough. It’s particularly common on rosés because they usually come in clear bottles. Dark green bottles help prevent this problem but dark amber is even better. Don’t buy any wine that you know has been sitting in a shop window especially in a clear bottle, it will almost certainly be ruined.

6. Corked

Known in the trade as TCA, an abbreviation of the compound lurking in the cork that causes it. According to Tom Stevenson roughly 3 percent of wines are corked. In most cases you will notice a strong smell of mold or wet cardboard. Some wines have TCA in such small quantities that you can only detect it by a lack of fruit rather than an overt taste of mold. If you aren’t sure if a bottle is corked, the best thing to do is get the waiter to try it. He should be familiar with how the wine is meant to taste. Though it’s usually caused by an infected cork, you can have TCA without a cork. In fact I’ve had garlic and carrots that smelt of TCA though I’ve never had the nerve to say, “waiter, take these carrots away, they’re corked!”

7. Mousiness

A few years ago I began to notice a new problem. The wine would smell normal and to begin with, it would taste fine. But then at the back of the throat I would get a stale yeasty flavor, or in the worst cases, a feral animal sort of taste. This is mousiness aka hamster cages or in French, goût de souris. It is caused by an infection of lactobacillus. The reason it’s become so common recently is the trend for low sulfur wine making. It’s the most frustrating fault because it could so easily be cured by using tiny quantities of sulfur. It’s the main reason that I am wary of natural wine especially as some people, including some winemakers and sommeliers, can’t detect it. The worst mousiness I’ve ever had was in Armenia which actually tasted like a rodent was rotting at the back of my mouth when I swallowed. The winemaker smiled at me and said, “good isn’t it? No chemicals.”