An instrument for measuring a refractive index, which is related to the amount by which the angle of a light wave is changed when passing through the boundary between two media. The amount of refraction is a convenient way to measure solute concentration of a solution and is widely used in viticultural and winemaking to follow the ripeness of grapes and changes during vinification.
Contrasts with protective and reductive winemaking in that the winemaker deliberately exposes the wine to oxygen at various stages in the winemaking process in order to encourage certain reactions and achieve a particular style of wine. Oloroso Sherry being an extreme example.
The connection of two pieces of living plant tissue so that they unite and grow as one plant, has been a particularly important element in growing vines since the end of the 19th century.
Chemicals applied to vineyards to control the growth of weeds. They may be either pre-emergent (or residual) or post-emergent (knockdowm). The latter group comprises two types, contact and syntemic herbicides. Residual herbicides act against germinating seedlings of the weeds, while post-emergent herbicides are applied only to the strip of ground directly under the vine, and weeds growing between the rows are controlled by cultivation or mowing.
Is hard and supple, and most oaks have watertight wood, which has the simple advantage over other wood types used for cooperage of displaying a natural affinity with wine, imparting qualities and flavours that today's consumers appreciate as enhancing or complementing those of many wines.
Often abbreviated to MLF or malo, is the conversion of stronger malic acid anturally present in new wine into lactic acid (which has lower acidity) and carbon dioxide.
French for "white of blacks", describes a white wine made from dark-skinned grapes by pressing them very gently and running the pale juice off the skins as clear as possibl.
Is a complex of sensations resulting from the shrinking, drawing, or puckering of the tissues of the mouth. The most important astringent materials are tannins.
Or insert, planks of wood, usually oak, placed in a stainless steel tank and held in position by a metal framework, are a way of imparting oak flavour to wine more cheaply than by fermenting or ageing in barrels since the staves are easily replaced.
Of a wine is ist total concentration of volatile acids, those naturally occuring organic acids of wines that are separable by distillation. Wine's most common volatile acid by far is acetic acid (more than 96%).
The greatest wine of Sauternes and, according to the famous 1855 classification, of the entire Bordeaux region it is sweet, golden, and apparently almost immortal.
Or Le Montrachet, the most famous Grand Cru white burgundy, the apogee of the Chardonnay grape produced from a single vineyard in the Côte de Beaune district of the Côte d'Or.
Term much used in the wine world, initially smoewhat patronizingly but with increasing admiration in the last quarter of the 20th century as the New World's share of global exports rose from 3 to 23%, to distinguish the colonies established as a result of the longer voyages in the 15th century.
Town north of Perpignan in southern France that gives ist name to two of the biggest appellations of Roussillon, Rivesaltes and Muscat de Rivesaltes, both of them vins doux naturels.
Or bâtonnage, as it is called in French, is the once fashionable winemaking operation of mixing up the lees in a barrel, cask, tank or vat with the wine resting on them. It is an optional addition to the process of lees contact and is often employed, particularly for whites which have undergone barrel fermentation. Usually done with a stick. Stirring up the lees in the barrel also effects oak flavour.
Sleep, the normal state of vines in winter. This period normally starts with autumn leaf fall, although buds are in a state of so-called organic dormancy from veraison onwards.
One of the two principal organic acids of grapes and wines. Ist name comes from malum, Latin for apple, the fruit in which it was first identified. Present in nearly all fruits and berries.
Increasingly popular and currently fashionable winemaking practice known to the Ancient Romans whereby newly fermented wine is deliberately left in contact with the lees. This period of lees contact may take place in any container, from a bottle to a large tank or vat-although a small oak barrel is the most common location for lees contact.
Meaning literally "yellow wine" in French, extraordinary style of wine made in France, mainly in the Jura region, using a technique similar to that used for making Sherry but without fortification.
Very large group of highly reactive chemical compounds of which phenol is the basic building block. These include many natural colour pigments such as the anthocyanins of fruit and dark-skinned grapes, most natural vegetable tannins such as occur in grapes, and many flavour compounds.
