"Patiently waiting to pour the rest of the table their glass of wine, the server looks to the host for a nod of approval.... "
Rest assured if you have a faulty wine, then you can return it to the place of purchase or refuse it at a restaurant. But first you must be able to recognize a fault. A wine fault is an unpleasant characteristic often resulting from poor wine making practices or storage conditions, and leading to wine spoilage. The tricky part about this is, many of the compounds that cause wine faults are already naturally present in wine but at insufficient concentrations to adversely affect it. Depending on your tastes, these attributes may impart positive characteristics, however in large quantities they can also make the wine less appealing. Kind of like weeds. Some weeds are really pretty but if they kill all your other flowers then not so much.
Environmental Issues "I think this wine is corked." Yes we've all heard it, also called cork taint and is recognized by a certain moldy basement, kitchen sink, dirty sock smell. This is a common fault. At varying levels, about 10% of wine (with a cork) is fated with it (one reason to support the screw top!). Cork taint is attributed to the compound trichloroanisole or TCA. TCA is a mold growth thought to originate in the cleaning process of chlorine bleached wine corks and barrels. The chlorine bleaching process ironically is used to sterilize corks! While this will not harm you, it won't taste good. However it usually tastes better than it smells. "This wine tastes cooked." Well it probably is. The ideal storage temperature for wine is generally 55 degrees F. Wines that have been exposed to high temperatures for one reason or another... in transit, left in the heat on a dock... left in a garage in the summer... stored in the cupboard above the stove...whatever the reason, will thermally expand and may even leak out. When opening a bottle of wine, be very wary if a track of wine is visible along the length of the cork, if the cork is partially pushed up, or if wine is visible on the top of the cork while it is still in the bottle. Most likely it has been damaged by heat. Often these wines become oxidized hence the color of red wine becomes more brick-ish. Which brings me to my next topic...
Oxidation Is said to be the most common wine fault. It doesn't take much for the process to occur; oxygen and a catalyst are the only requirements. Oxidation takes place throughout the wine making process, and even after the wine has been bottled. The oxidation of phenols in wine leads to loss of color, flavor, and aroma, or in other words the wine is "flat". There are a number of oxidation processes that can occur but most notably they are responsible for sour, metallic, nail polish remover, glue, varnish, or vinegar aromas and flavors. However to combat oxidation, some wine makers add anti-oxidants to wine, one very common one is sulfur dioxide....
Sulfur in various forms is added to wine and used in the vineyard as an antimicrobial agent and as an antioxidant. There are 3 sulfur compounds of note, all very different. Sulfur dioxide (a sulfite) is a preservative. Usually in the form of a powder and used in lots of food especially dried fruit and processed meats. However when it is overused in winery, your wine will be reminiscent of the bathroom after a match is burnt or mothballs. These wines are often called "sulfitic". Hydrogen Sulfide is totally different! It is a gas. It is a natural bi-product of yeast metabolism. However if the wine maker fails to control this your wine will impart a very distinct rotten egg aroma, the smell of Yellowstone Natl. Park in your wine glass. Even worse, Hydrogen Sulphide can further react to form mercaptans. Mercaptans cause wine to have skunky, oniony, and rubber refinery aromas. Very bad! So yes sulfur can be confusing, is it good or bad? Sulfur itself is a basic element, a soil and plant nutrient, long used as a natural fungicide in the vineyard. So just remember too much of a good thing is not a good thing and parents aren't always to blame for their offspring... but their spouse might be... just kidding :-) And finally the last fault that we are going to discuss today...
Re fermentation is caused by yeasts re fermenting residual sugar after the wine is bottled. Fermentation is when yeast eats sugar to form alcohol, CO2, and heat. So if there is re fermentation, their will be a spritziness to your wine because the CO2 is trapped in the bottle until you open it. This is actually how champagne bubbles are made, however unplanned re fermentation will result in volatile flavors as well as the spritziness.
So now not only can you drink to your health, you can drink to the health of your wine!!!
cheers-
Jessica
