W.C. Paetz / HRT333 / Wine Judging / September 23, 2002

Wine Faults Introduction:

Why should we care about wine faults? The subject of wine faults will offer us critical information necessary to assess the status of a wine with knowledge, insight, sophistication and confidence.

As consumers dining in a fine restaurant, we absolutely should know why we are rejecting an expensive bottle. The more specific our rationale, the more credibility we will have when we send the sommelier back to the wine cellar for another bottle.

As wine makers we should be especially interested in not only the criteria for detection of wine faults but also for knowing what preventative measures can be taken to preclude or correct them.

Wine Faults Discussion:

One intriguing paradox regarding wine faults is the fact that they are somewhat subjective. Certainly we should strive to understand the composition of well made wines. We should aspire to know just how a good wine characteristically tastes. We should know the expected color, aroma and bouquet. We must develop or adopt a wine philosophy that can be consistently applied and sustained. This is the crux of wine fault identification. Our perception of a wine fault may not correspond to another individual who has a different tasting threshold or perhaps a different palate.

In some instances we may not even be able to detect a particular wine fault. In such instances, I believe a case may be made suggesting if the wine fault does not diminish the enjoyment of the wine, then there is no wine fault.

Wine faults are attributable to several factors and may not necessarily implicate the enologist that vinified the wine. Time may have something to do with the deterioration of characteristics such as color, taste and bouquet.

Ironically many wines are improved by bottle aging. It could be that poor cellar conditions caused the wine to go bad, storing a wine in an environment with fluctuating temperature and humidity extremes as well as exposure to constant vibrations can cause a wine to rapidly age. The concurrent lack of elasticity of the cork may become a factor that allows oxygen to come in contact with the wine. The cork may have defective lenticles in its composition which facilitates contamination by the cork to taint the wine. Improper storage includes the failure to lay the bottle on its side, which if done would preclude the drying out of the cork.

There are some wine faults that are preventable by the careful professional enologist. The two most common wine faults recurring today are corked wine and oxidized wine.

The culprit in a corked wine is “trichoroanisole”. This substance is from a chemical reaction to chlorine cleaner used to sanitize the cork material prior to insertion in the bottle. The corked wine will smell dank and taste musty or moldy. It can appear faint or strong and may overpower the fruity flavor usually found in the wine. A cork infection unfortunately can not be corrected and the wine should be discarded. The issues surrounding cork use include the tactile pleasure and ceremony that traditional wine closures have offered for centuries. The solutions include twist cap closures as well as various alternative materials being used to make corks. Is this a decision of the wine maker?

Oxidized wine is caused by inadvertent exposure of the wine to oxygen. The wine maker should protect the wine from this malady every step of the way from harvest through bottling. Prudent vintners will harvest and immediately press the grapes allowing little or no time for exposure to air. Sometimes refrigeration is necessary to preserve the freshness of the fruit. The must may be protected with a blanket of nitrogen until fermentation starts and co2 covers the wine. An immediate protection is sulfites or meta placed in the must immediately after crushing. White wines are especially susceptible to oxidation. When oxidation takes place the wine color will be darker and some of the fruitiness will be lost. White wines will proceed from green or pale straw to yellow, gold and then dark amber. Red wines proceed from deep purple red to brick red to orange to brown. These are visual symptoms of oxidation and aging of wines. The wines usual fruity flavors may be lost and replaced with sherry or maderized flavors often including nuttiness.

Sulfur Dioxide, the smell of a burnt match is a readily identifiable wine flaw attributable to excess sulfur in the wine. When a wine is low in PH it is especially vulnerable. In our cold climate most of our fruit will have high acid content and the need to add sulfur is not as frequent. Sulfur is used to protect against oxidation and to kill unwanted bacteria but too much can cause rotten egg or burnt match smells. The enologist must monitor the free sulfur in the wine throughout the fermentation process. If the smell is not too excessive allowing the wine to breathe may clear it up.

Over oaking is a wine fault that is dependent upon the perception of the consumer. The rich vanilla buttery flavor components of toasted oak are recognized as desirable by many consumers. The level of flavor will depend upon the type of oak. New barrels give more flavor than used ones. The time spent in the barrel. The size of the cask, the bigger the cask the less wine to wood ratio. The main types of wood used are French, American and increasingly Eastern European Oak. Some coopers in Michigan are choosing our indigenous oaks for their barrels. The toast status of the barrel will flavor differently. Ultimately this may be a wine fault or desirable attribute dependent upon the individual tasters' preference.

Diamonds in your wine? Can this be a fault? Tartrate crystals come from tartaric acid which gives freshness to the wine. These small precipitates are found in some wines. They are completely inert and may be decanted or consumed. To avoid these the wine maker may choose to put the wine through cold stabilization or fine filtration to remove the tartrates.

Wine Fault Conclusions:

As an amateur wine maker, I have had several vintages subjected to professional critiques. They always use euphemistic language to tell you what is wrong and they never tell you what you need to do to correct your vinification process. This wine fault exercise has accomplished that and more.

Unfortunately for the many individuals, who have not had the opportunity to study and understand wine faults, they may be unwitting consumers who purchase wine based upon irrelevant criteria and may never realize they are failing to optimize their enjoyment of this complex beverage.

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