David’s article as prepared for the Duluth News Tribune for the column which ran on 7/22/2015:
Ordering a bottle of wine in a restaurant includes the moment when the server brings the bottle over to the table and presents a small sample of the wine to the customer. Most people think that this is their opportunity to determine if they like the wine. They assume that if they don’t like it, they can return it for a bottle they do like. This is not true. Once the bottle is opened you’ve bought it. If you don’t like it, too bad. But if the wine is faulted, and you can articulate this to the server, they should bring you another bottle that is absent of fault.
A wine can become faulted in many different ways and each fault smells different. Here are the most common wine faults.
- Corked or Cork Taint – the aroma of moldy basement or wet cardboard. This is the most common fault noticed when evaluating a wine because the human nose is particularly sensitive to this aroma. Most people can smell cork taint at concentrations of 2 – 7 parts per trillion. This fault is caused by a natural mold that inhabits the bark of the cork oak tree. This mold readily interacts with other compounds found in wine and produces an aroma called 2,4,6-trichloroanisole (TCA). TCA can infect winery equipment such as barrels, boxes, and even walls, making every wine consumed susceptible, even those capped with screw caps or synthetic corks.
- Bacterial Action – the aromas of vinegar, rancid cheese, sauerkraut, goat, fingernail polish, or crushed geranium. Most of these smells would occur independently of each other but they are all the effect of an incomplete or improper secondary bacterial fermentation. The two main culprits are lactic bacteria and acetobacter and if left in a wine with sufficient concentration they will produce undesirable aromas.
- Odors from Sulfur – the smell of a burning match, rotten eggs, garlic or onions. These aromas can occur if sulfur dioxide (SO2),which is used to stabilize wine against bacterial infection, is added in too high of a concentration, or if the wine has sit too long in a complete absence of oxygen. This might occur when a bottle is sealed with a screw cap, rather than a cork which allows for a tiny amount of oxygen exchange through the cork. The odorous smells can also occur if sulfur combines with ethanol in the bottle, forming a new compound called ethyl mercaptan. Ethyl mercaptan is the same substance which is added to odorless propane and natural gas. No one wants to drink a wine that smells like propane.
Odorous faults caused during harvest or production.
- Green: The odor of leaves from the use of underripe grapes.
- Oxidized: Exposure to oxygen resulting in nutty, caramelized, fruitless aroma.
- Moldy: The use of moldy grapes or barrels.
- Rubbery: The smell of tires or rubber which is associated with low acidity or excess sulfur.
- Stagnant: The smell of stale water.
- Maderized: The smell of cooked fruit. This often results from improper storage in a warm location or from excess heat during transport.
- Brett: This is a yeast that can infect a winery and cause the wine to smell sweaty or like a horse or even slightly medicinal like a Band-Aid.
You’ve probably noticed that the way to identify each of these faults is through smelling the wine. That’s because 80% of tasting is smelling. Next time you are asked to evaluate the wine you’ve ordered at the restaurant, take your time, swirl the wine in the glass, take a big sniff and try to recognize the aromas. If something smells off to you, inform your server. You might have a faulted wine.
Lastly, while a wine might smell bad and thus we would consider it faulted it is still drinkable. None of these faults will harm any part of you, except maybe your sense of smell.
David Devere is a certified specialist of wine. He teaches wine classes mainly in the Duluth, MN area. Contact him at firstname.lastname@example.org.