Wine Storage Glossary
Vintage Cellars defines some common wine storage terms. Wine storage information from the wine storage specialists.
Appellation D'Origine Controlee
"Controlled origin". French law specifies the regions and methods which can produce wine that is labeled with particular regional information. Similar regulations are applied to some cheeses and other agricultural products affected by terroir.
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Balance
The four main components of a wine's flavor are sweetness, alcohol, tannins, and acid. The interplay between these four components is what forms the primary tastes of the wine. Acidity counteracts sweetness and alcohol, and fruitiness counteracts tannins. A balanced wine has a harmonious level of all of these components, without one standing out and dominating the rest. An unbalanced wine could be harsh or bitter (tannins in dominance), cloying (sweetness in dominance), acidic (acids in dominance), etc.
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Body
Wine can range from light-bodied (feels more like water in the mouth) to full-bodied (feels thicker, more like milk). See also: Mouthfeel.
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Bordeaux Bottles
The traditional shape of wine bottles, with high straight sides and a short taper to a thin neck. 750 mL Bordeaux bottles will fit into all standard wine racks. See also: Standard bottle.
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Burgundy Bottles
A more tapered shape than Bordeaux style bottles, with a long slope to the neck and less-pronounced "shoulders".
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Champagne Bottles
A shape similar to the Burgundy bottle, but with thicker walls to contain the higher pressures. Champagne bottles may not fit into some standard wine racks.
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Corked
This refers to a bottle of wine that is tainted due to damage, drying or microbial action in the cork. The condition is usually noticeable by smell, color or taste of the wine and is also known as cork taint. Some causes of corked bottles are avoidable by storing wine properly, but at other times the condition is not preventable.
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Fortified Wine
Wine with additional alcohol added, often in the form of spirits like brandy. Examples include port, sherry and vermouth.
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Humidity
A relative humidity of around 70% is ideal for aging wine. A too-humid environment will cause mold to form on the cork, possibly contaminating the wine. Not enough humidity, and the cork will dry out and crack. A too-dry environment will also cause wine to rapidly evaporate from the bottle, creating a vacuum that sucks in oxygen-rich air. Any of these conditions will result in a bottle that is "corked"--tainted due to cork failure. Humidity can be added using an integrated humidifier such as that available in CellarPro cooling systems, a separate humidifier such as the Wine Guardian through the wall humidifier or with decorative humidifier fountains.
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Insulation
Insulation is important to wine cellars and wine cabinets. Made of materials that resist the transfer of heat, insulation keeps your cold things cold and your warm things warm. Heavy-duty insulation may be required in wine cellars to maintain proper temperatures. Skimping on the insulation phase will lead to overworked and inefficient cooling systems. Money spent on insulation is money saved down the line. Foam board insulation is commonly used in wine cellar construction.
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Magnum
A large format bottle size, holding about 1.5 liters, or twice the size of a standard bottle. May require special magnum racking.
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Meritage
a trademarked term used for American-made Bordeaux-style wines so as to not interfere with the AOC regulations regarding Bordeaux. The term was developed as a way to give a recognizable name to high-quality blended wines that don't qualify for varietal labeling. Red Meritages must be made from at least two of the following, with less than 90% of any one grape in the mix: Cabernet Sauvignon, Merlot, Cabernet Franc, Petit Verdot and Carmenere. Similarly, whites must contain at least two of these: Sauvignon Blanc, Semillon, Muscadelle du Bordelais; with no more than 90% of any single variety.
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Methode Champenoise
The traditional method of secondary fermentation by which Champagne is made. After initial fermentation, yeast and sugar are added and a secondary fermentation occurs, after which the yeast is removed, more sugar is added (usually) and the Champagne is aged before releasing for sale. Outside Europe, sparkling wines made by this method may be labeled "traditional method" or "methode traditionelle".
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Mouthfeel
Refers to how a wine feels in the mouth, from light and crisp to heavy and thick. See also: Body.
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Nucleation
The process of bubble formation when pressure is released, as seen in Champagne and sparkling wines. This happens more readily on some surfaces, leading glassmakers like Riedel to laser-etch their Champagne glasses to encourage nucleation.
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Oxidation
Oxygen is both the friend and the enemy of aging wines. Oxidation is the process by which exposure to oxygen changes the chemical properties of some wine components. This smooths flavors over time, resulting in the decidedly un-grapelike flavors of older wines, especially red wines. Oxygen reacts with flavor components and also with alcohol, which can result in vinegary flavors if too much oxygen is permitted.
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Red Wine
Red wines are made from red or purple skinned grapes, and the color is partially determined by the length of time the juice stays in contact with the skins during crushing. They are best stored at about 55 degrees and served at 60 to 65 degrees F. Red wines tend to benefit from aging, becoming smoother and mellower with time. Popular red varieties include Merlot, Cabernet Sauvignon, Pinot Noir, and Zinfandel.
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Sediment
Sediment is a gritty substance that can form in the bottom of bottles that are aged for a long time, usually red wines. It is created when tannins undergo polymerization, binding together in long chains that then settle out as sediment. Decant wine to keep sediment out of your glass.
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Split Bottle
A small bottle of wine, holding (usually) 0.5 liters of wine. May not fit into all racking systems.
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Split System Cooling
Split system wine cooling units are commonly used when placing the entirely of an evaporator/condenser system inside the building is undesirable. They are both quiet and unobtrusive, because only the intake and outtake grills will be visible in your cellar and the condenser is situated outside your cellar for noise reduction. The first component of split system wine cooling units is an evaporator coil installed in the wine room or wine cellar. The evaporator coil circulates cold air and controls the humidity. The second component of split system wine cooling units includes a compressor, condensing fan, and coil. This unit is installed outdoors or in an adjoining room and requires ventilation. The two sections are connected by refrigeration lines. See our split system cooling units for details and diagram.
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Standard Bottle
The usual size for wine bottles, 750 mL, or 3/4 of a liter. These may be Bordeaux, Burgundy or Champagne shaped bottles (or more unusual shapes).
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Tannins
Tannins are a phenolic compound and very important for wine aging.. Tannins create the astringent flavors in reds--the dry, bitter flavors. Wines high in tannins go well with red meat and high protein dishes, because tannins like to bind to proteins. As wines age, the tannins polymerize, binding together in long chains. The chains become sediment in the bottom of the bottle, and the flavor of the wine becomes more smooth and mellow due to the lower tannin content. Tannins also bind to other aromatic compounds in the wine, preventing those flavors from evaporating. Oak barrel aging increases the levels of tannins.
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Temperature
Wine ages best in cool temperatures--approximately 55 degrees F. A temperature of 55° is the perfect environment for the chemical reactions that result in good wine. But it's too cold to allow other, undesirable reactions that can give a wine unwanted aromas. Even a short exposure to extreme temperatures can trigger unwanted reactions and ruin the wine. Wine ages best at a temperature that is both cool and constant. Choosing the correct wine cellar cooling system or wine cabinet for your storage location will ensure proper temperatures for your collection.
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Temperature Differential
This refers to the ability of a cooling or refrigeration system to deal with ambient temperatures. The temperature differential is the number of degrees higher the ambient temperature can be than the desired 55 degrees without overtaxing the unit. For example, if a cooling unit has a temperature differential of 40 degrees, the temperature outside the cooled space should not be more than 95 degrees if one wishes to maintain a 55 degree storage temperature for their wine.
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Terroir
A French term related to "terre"--land--that denotes the particular characteristics imparted by specific geographical regions due to differences in farming practices, soil quality (aeration, mineral content, water availability) and weather. The concept of terroir is the basis for the AOC regulations that restrict the labeling of wines like Champagne.
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Thermoelectric Cooling
A method of cooling that uses the Peltier effect to provide cooling. Thermoelectric wine coolers are very energy-efficient and produce no vibration, so as to leave sediment undisturbed. See also: Full article on Thermoelectric vs Vapor Compression.
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Universal Racking
Used to describe the type of wine racks used in a wine cabinet. Universal racking indicates that most bottle sizes will fit, including standard Bordeaux bottles and larger, curvier Champagne bottles. Magnums and split bottles generally will not fit, unless specified.
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Vapor Barrier
A vapor barrier is a moisture-proof layer that is added during the insulation phase of construction. Some insulation incorporates a vapor barrier. The barrier must be installed on the "warm side" of the insulation (ie outside your wine cellar) to prevent condensation. It is common to install a vapor barrier by wrapping the room in plastic during the insulation phase. A vapor barrier is very important to prevent moisture damage to your wine cellar or surrounding areas. See also: insulation.
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Vapor Compression Cooling
Vapor compression cooling works just like your kitchen refrigerator. A compressor pushes the molecules of the refrigerant together, which causes a temperature increase, then cools the refrigerant vapor slightly without allowing it to expand. Then it is expanded in the evaporator, becoming extremely cold and cooling the air that is blown over the coils of the evaporator. Vapor compression cooling is effective but not efficient. See also: thermoelectric cooling.
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Varietal
A wine made from only (or primarily) one variety of grape rather than a blend of several varieties. Should not be applied to the types of grape (those are "varieties"), only to the wine made from a single variety of grape. Varietal wines must generally contain a minimum of 85% of a given grape variety to be named as such, and in many countries an even higher percentage is required.
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Vintage
Wine made from grapes that are all from a single vineyard or area in a single year (a "vintage wine"). Can also be applied to the grapes from a single year ("this vintage made particularly good wines"), or refer to the year and location of bottling ("What vintage is that?" "It's a '92.").
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White Wine
White wines are made from yellow or green skinned grapes, or sometimes from skinned red grapes. They tend to have lighter, crisper flavors with less tannin content than red wines. White wines are best served at 45-55 degrees F. Popular white wines include Chardonnay, Sauvignon Blanc, Riesling, Gewurztraminer, Pinot Gris and Pinot Grigio.
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Wine Cellar
A climate-controlled room or cabinet designed to maintain the correct temperature (around 55 degrees F) and humidity (around 70%) to properly store and age wines. Wine cellars have existed in some form for thousands of years. Modern technology now allows an extraordinary level of precision in maintaining the conditions in wine cellars. Necessary components generally include a cooling system, insulation, racking and insulated doors.
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