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- Acetic Spoilage
Results from the oxidation of ethanol (alcohol) to acetic acid (the acid component of vinegar), which is then transformed by the acetic bacteria to an ester called ethyl acetate. The prevalent characteristic is an odor of vinegar and a bitter, dry taste.
- Alcoholic fermentation
The transformation of reductive sugars into alcohol (essentially ethanol) by fermentation yeast (mostly saccharomyces cerevisae). There is also a production of carbon dioxide during the alcoholic fermentation.
Components which secure oxygen and protect wine from the problems of exposure to oxygen (oxidation). Sulfur is used for its anti-oxidative qualities, as is ascorbic acid, the latter being reserved for the bottling.
Unicellular micro-organisms which multiply by division. The most common in wine are the leuconostoc oenos and lactobacillus (agents of the malolactic fermentation) and acetobacter (responsible for acetic spoilage).
- Barrel or cask
A generic term for a barrel usually made of oak which is meant to hold wine or eau-de-vie. Each region has a specific name for their barrel, and contains a slightly different volume: In Burgundy a pièce or barrique holds 228 liters, in Bordeaux 225 liters. A feuillette holds 114 liters.
Consists of mixing or blending together different cuvées of a wine to obtain a specific taste and texture with a balance of tannins, acidity, fruit, etc. A practice which is not as common in Burgundy as it is in Bordeaux due to the use of one red and one white grape varietal in Burgundy.
- Botrytis cinerea
A fungus that may develop inside or outside the grape berry and is responsible for rot which is harmful to the organoleptic characteristics (taste) of wine (loss of color in reds, risk of oxidative instability in whites). The development of botrytis cinerea is, however, desirable in some vineyard areas like the Sauternais or even in some small villages of the Mâconnais. This fungus concentrates the constituents of the grape berry, increasing the sugar content, enabling the production of sweet desert wines.
Originally a wooden cork used to seal the hole on the side of a barrel. Progressively the silicon bung has replaced the wooden as it is more hygienic and hermetic.
In the fermentation of red wine, the mass of grape solids (skins and stems) that accumulate at the top of the fermentation tank. The solids rise and form the cap due to the production of carbon dioxide (CO2) during the alcoholic fermentation.
- Cask or Barrel
A wooden barrel made of oak of different origins (Vosges, Allier, Tronçais, etc.), containing 225 liters in Bordeaux and 228 liters in Burgundy.
An operation consisting of adding sugar to must during the alcoholic fermentation to increase the degree of alcohol. This practice has been used since the 18th century and is named after Mr. Chaptal
- Clarification by sedimentation
An important step in the vinification of white wine in which the bourbe (particles present in the freshly pressed must which are not necessarily desirable) are allowed to deposit to the bottom of a tank .The must is racked off of the deposit (bourbe) before the alcoholic fermentation. This process is often facilitated by cooling the must to 12°C (around 55°F) for 24 hours.
The object of crushing the grapes is to liberate some of the juice before the maceration. In red wine this permits a better, more even fermentation as the ratio of juice to skin is increased. In white wine crushing the grapes facilitates the pressing. A crusher is generally equipped with two rotating crushing cylinders which rotate in opposite directions and between which the grapes fall. Very often the crusher and destemmer are part of the same machine, the grapes first going through the crusher, then following through the destemmer or vice-versa.
A mechanical procedure in which the grape berries are separated from the stalks. Whether partial or total destemming is done, this procedure is recommended for bunches whose stalks are not lignified (still green).
Organic substances in the protein family which are naturally present on a grape and which happen to be biological catalyzers. The use of additional enzymes in winemaking is permitted under strict conditions and is highly regimented. Enzymes prepared for enological use guarantee for example, a more profound extraction of color in red wines.
Unlike fining, filtration is a mechanical procedure which clarifies wine, rendering it limpid. There exist several different techniques of filtration, some which guarantee microbiological stability (yeast and bacteria are eliminated), but these are said to strip the wine. Many estates in Burgundy choose to no longer filter their wine, or to filter only when necessary rather than systematically.
This is a method of clarifying and stabilizing wine with the use of a fining agent. The fining agent enables a coagulation of the insoluble particles in suspense in the wine, which deposit at the bottom of the barrel. In white wine, for example, bentonite attracts protein. In red wine, egg whites work well in precipitating excess tannins.
- Free-run wine
The wine that is collected by gravity at the end of the alcoholic fermentation when the (red) wine and marc are taken out of tank to be pressed.
- Inert gas
Carbonic gas or nitrogen used to separate and protect wine from air. This gas acts as a protective cushion from the oxidative hazards due to contact with air. A mixture of carbon dioxide and nitrogen is most commonly used today.
- Lactic disease or spoilage
An alteration of wine carried out by the lactic bacteria which transforms residual sugars to lactic and acetic acid.
- Lactobacilles, Leuconostocs
Bacterial agents that are naturally present on grape skins and are responsible for the malolactic fermentation
- Lignified, matured
Describes a state of complete development of a vine shoot (occurring in August). The lignified structure gives a wood aspect to the shoot.
- Malolactic fermentation
This is not a strict fermentation but rather a breaking down or transforming of the malic acid (a diacid) in a wine to lactic acid (a monoacid) through the action of lactic bacteria. This is a natural de-acidification of the wine. As in the alcoholic fermentation, carbon dioxide is also produced during the malolactic fermentation.
The solid matter that remains after pressing the grapes, consisting of the skin, stocks and seeds.
A form of sulfur (potassium salts) used during vinification because of its antioxidant and antiseptic properties.
- Mildew, brown-rot
A cryptogamic vine illness due to a microscopic fungus. The leaves are effected first, showing white patches on the underside which limits nourishment to the grapes. The stems and in severe cases even the grape bunches might be attacked by mildew.
An enzyme that acts as a catalyser of the oxidation of wine, particularly when there is rot in the crop. Oxidase is a product of noble rot or gray rot, secreted by botrytis cineria.
Represents the real acidity of a wine by measuring the ions H+ liberated by the wine's acids. The acidity of Burgundy wine varies between pH 2.9 (more acidic) and pH 3.4 (less acidic).
- Phenolic componants
Encompasses the two large families of components which are particularly important in red wine: anthocyanes (color component) and tannins (which give structure, sometimes even astringency to the wine). The development of these components is a function of the maturity of the grapes. Furthermore, the phenolic maturity informs the grower and helps in determining the harvest date.
- Powdery mildew
Like mildew this is a cryptogamic illness which can cause severe damage to the vine. Powdery mildew is a gray fungus that forms on the leaves and grapes. The grapes eventually split and shrivel.
Wine obtained through pressing of the marc (stems and skins). The content of tannins and anthocyanes in the vin de presse is higher than in the vin de coule (free-run wine).
- Pumping over
A technique used during the vinification of red wine which is done to homogenize the contents for a smooth fermentation and to increase the extraction of color and the phenomena of the juice / skin maceration. The technique consists of pumping (with or without contact to air) the juice from the bottom of the fermentation tank over the top.
- Punching the cap
An operation carried out during the alcoholic fermentation of red wine consisting of punching down the cap of the marc (solid matter) at the top of the fermentation tank into the juice below. This is done to homogenize the contents for a smooth fermentation and allow better extraction of the phenolic components contained in the skins. At one time this was done by hand only, with the use of a "pigeou" or simply with the feet. Today in larger wineries the pigeage is often automated.
Separating the clear wine from the lees deposited at the bottom of the barrels or the cuve. Several techniques exist: the traditional method of a burgundian "pièce" is done with a fountain spicket placed in the hole in the side of the barrel. The barrel is then inclined gently and the wine is allowed to pour into another vessel until it begins to run clear. At this point the racking is stopped.
A plank of wood which has been slightly curved by heat to give the shape necessary to construct a wine barrel.
A plank of wood that has been split and dried (seasoned) for a specific number of years and which will become a stave for a wine barrel.
- Stocks and stems
The wood-like stems to which the berries are attached.
- Sulfuring of barrels
Originally consisted of burning a sulfur wick to disinfect an empty barrel before filling it with new wine. This is a very important operation as it avoids the development of undesirable bacteria (like acetobacter). Today the wicks have been replaced by tablets.
As with the anthocyanes, tannins belong to the phenol family. Being electronegatively charged in the wine, the tannins partly precipitate with egg albumin(whites). They are responsible for the astringency in wines, but also for much of the structure.
Originating from the precipitation of the tartaric acid in wine as potassium bitartrates or calcium tartrates, these tartrates settle in crystal form at the bottom and on the sides of tanks and barrels, or sometimes even the cork. Tartaric stabilization has become common practice (particularly at cold temperatures) and avoids the eventual crystal tartaric deposits at the bottom of a bottle (which has no consequence to the wine).
- Topping up
Topping up barrels from which wine has evaporated through the pores of the wood. Topping up avoids contact between the wine and air, keeping it safe from oxidation or spoilage.
Visual and textural changes in a wine that are characterized by the development of a haze or deposit. These changes are provoked by high levels of iron, copper or proteins and can be triggered after being exposed to air, light or heat. The four common casses are oxydasiqe, protéique (protein), ferrique (iron) and cuivrique (copper).
A vine varietal essential for the production of wine grapes. All varietals planted in France (Chardonnay, Pinot Noir..) are of the Vitis vinifera gender.
- Verjuice or unripe grapes
In Burgundy, the bunches which are found on the auxiliary shoots (branches) which mature later than those on the principal shoots and, so are more acidic. They used to serve as culinary condiments.
- Vin de saignee
A portion of the juice in a tank is run off before the alcoholic fermentation begins. In doing so the proportion of juice to solid matter (skins) is decreased and the extraction is increased.
A hydra-alcoholic beverage obtained exclusively from the alcoholic fermentation of grapes or fresh grape juice.
Microscopic unicellular organisms of which the Saccharomyces cerevisae is responsible for the alcoholic fermentation. Other undesirable yeast also exist in wine which are capable of generating off flavors: S. Brettanomyces is responsible for sweaty-horse type odors.
- Yeast inoculation
A practice which consists of adding commercially prepared yeast to the grape must to start up fermentation, or during fermentation to lengthen it. Many estates prefer to use a pied de cuve, which is a yeast culture made from indigenous yeast.