Wine-Searcher Technical Wine Terms A to B

'A'

• Acidification: the practice of artificially increasing the acidity of grape must by the addition of tartaric, citric or malic acids. It is most prevalent in warm wine regions where the grapes' natural acids (mainly malic acid) tend to degrade during the ripening process. If acidification is not artificially adjusted, the resulting wine will have a subdued fruit quality and be vulnerable to bacterial spoilage.
  
  
• Acidity: a general term associated with the sour and tart taste in grape juice and wines, caused by the presence of organic acids such as tartaric, malic and citric acids. Acidity in a final wine can also be the result of acidification (see above).
  
  Acidity has vital implications for the quality of wine, affecting balance, freshness, color preservation and ageing, as well as acting as a natural preservative.
  
  
• Alluvial: refers to a fertile soil type made up of fine-grained elements such as clay, sand, silt and sometimes gravels or stones. Alluvial soils are created when these sediments are deposited by flowing water.
  
  
• Altitude: refers to the height above sea level of a particular geographical location (a large region, sub-region or even a vineyard site). Altitude often has a marked effect on a wine's quality.
  
  Firstly, the higher a vineyard location is, the cooler the air temperature will be. (With every 330 ft/100m of height, the temperature generally drops by about 1.1F/0.6C.) This will delay the ripening or, conversely, lengthen the growing period. This ensures that the grapes can benefit from a longer hang time, which helps the accumulation of those vital chemical compounds (acids, sugar, color compounds) that define a grape's profile. However, lower temperatures can hinder ripening so these regions are generally suitable for cool climate viticulture. Altitude also affects the intensity of sunlight, so on a clear sunny day the vines on a higher site will enjoy more intense sunlight than those down on the plain.
  
  
• Amontillado: Amontillado is an amber-coloured sherry that sits somewhere between fino and oloroso on the sweetness spectrum. Amontillado starts out as a fino, but as the yeast dissipates the wine is fortified to approximately 17.5% alcohol to prevent rapid oxidation. Long barrel-ageing results in a darker color sherry with hints of the flor characters.
  
  
• Anthocyanins: naturally occurring phenolic compounds responsible for the red and purple color of many fruit and vegetables, including red grapes.
  
  
• AOP: stands for Appellation d'Origin Protegee, the European-level equivalent of France's AOC (Appellation d'Origin Controlée). It is the highest level of the French wine hierarchy. An AOP/AOC classification shows that a wine has been produced under specific legal quality-control requirements, and also acts as an indicator of provenance. The terms 'Grand Cru' and 'Premier Cru' denote a particularly high level of quality in an AOP/AOC wine.
  
  
• Appellation: An appellation encompasses the wine and labeling laws of a particular geographical area, including clearly delineated regional boundaries and specifications for vineyard and winery practices. In many traditional wine-growing countries, such as France, the appellation may also indicate the quality and style of the wine.
  
  
• Aromatics: a generic term referring to the grape varieties that produce distinctly aromatic wines. More specifically, it is used for the fruity and floral aromas produced by white grape varieties such as Riesling, Viognier, Muscat and the Traminer family (especially Gewurztraminer).
  
  
• Aspect: a geographical term indicating the direction in which a slope faces and an important factor of terroir; the aspect of a vineyard site determines the levels of sunshine it will receive and at what time during the day. The ideal aspect for a vineyard site is dependent on a number of environmental factors, and also the grape varieties grown. For most northern hemisphere vineyards a south-easterly aspect is ideal, as it exposes the vines to gentle morning sunshine for as long as it is available. Aspect is particularly important in cooler regions, where grapes can struggle to fully ripen.
  
  
• AVA (American Viticultural Area): a geographical area in the United States of America designated as a suitable wine-growing region. The boundaries of these regions are defined by the Alcohol and Tobacco Tax and Trade Bureau (TTB).
  
  

'B'

• Barrel fermentation: a winemaking technique in which grape juice is fermented in oak barrels in order to integrate the flavours of the wood with those of the grape. The lees, or yeast solids that remain after fermentation are also thought to impart a softer mouthfeel to the wine.
  
  
• Barrel maturation: a step in the winemaking process where wine is stored in oak barrels after fermentation has finished. With barrel maturation, the winemaker aims to combine flavor of the oak with that of the wine to produce more complex aromas. Barrel maturation is also important in softening the harsh tannins in young red wines and stabilizing color.
  
  
• Battonage: a winemaking term of French origin, battonage is the stirring of lees in a tank, vat or barrel, with the aim of increasing the flavor and aroma complexity of a wine. Traditionally done with a wooden baton, whence the name
  
  
• Botrytized: mostly refers to the sweet/dessert wines made using grapes affected by the fungus Botrytis cinerea. In its desirable form, the condition is also known as 'noble rot'. As the affected berries split they lose moisture, resulting in a higher percentage of solids in the grapes which produce wines high in residual sugar and concentrated flavor.
  
  
• Brettanomyces: often abbreviated to brett, is a spoilage yeast that causes mousey, farmyard and band aid-like aromas in a wine. It is not brett that causes these unpleasant aromas but the phenols formed by brett: 4-ethylphenol ( 4EP) and 4-ethylguiacol (4EG). In small amounts, brett can add complexity but in some wines, it can be overpowering. Poor cellar hygiene is often blamed for brettanomyces infections but high pH wines and warm storage temperatures also play a part. The yeast is very sensitive to sulphur dioxide and can be inhibited with a judicious dose of SO2 as well as maintaining cool cellar temperatures. If it does infect the wine, it is almost impossible to eradicate. However, sterile filtering before bottling can prevent further deterioration. Some producers try to rid their wines of ‘bretty’ smells using reverse osmosis. In addition, dimethyl dicarbonate (DMDC) is a sterilant used by some producers to prevent the growth of brett in bottle. However, it cannot be added to wine in the European Union. Once a barrel has been infected with brett, the barrel should not be used again. However, a number of producers had used ozone to clean infected barrels and free them from contamination.