The Wine Rack - Fine Wine, Liquors and Beer

Wine Terms

Acid

Grapes' acidity is derived mainly from Tartaric and Malic acids. Cold-climate grapes are generally high in acidity while those from warm or hot climates may suffer from low acidity.

Acidity

The quality of tartness, sourness and sharpness.

Appellation

A recognised wine-growing region.

American hybrid

Grape varieties which have been crossbred from American and European vines.

Ampelography

The science of identifying varieties by appearance with the leaves as the primary identifier.

Anthocyanins

Phenolics which strongly influence a wine's colour.

Ascorbic acid

Vitamin C which is sometimes added to wine during fermentation to slow oxidation.

Barrels

Vessels used for the making or maturation of wine. These may be of cement, plastic, stainless steel or oak. Oak barrels allow the wine to mature and breath while adding natural tannins and flavours such as vanilla or toast.

Baume

A measure of the sugar concentration in the juice or wine.

Botrytis

A fungus which may cause bunch rot and wine spoilage. In controlled situations, called noble rot, it can lead to concentrated sugars in the berries and delicious sweet wines can be made.

Brix

A measure of the sugar concentration in juice or wine.

Canopy

The above ground parts of the vine, especially the shoots and leaves.

Canopy management

A range of viticultural techniques used to manipulate the vine canopy. This is done for vine shape, interception of sunlight and disease control.

Cap

The thick cap of grape skins floating on top of the fermenting red wine.

Carbon dioxide

The gas given off during fermentation which is responsible for the bubbles in sparkling wines.

Carbonic Maceration

When whole bunches of grapes are allowed to ferment to produce an early-maturing wine style such as Beaujolais.

Chaptalization

The addition of sugar to wine. An illegal practice in Australia.

Clarification

To make a wine clear through fining, filtration and refrigeration.

Clone

A grape variety which has undergone some genetic adaptation from the original.

Cultivar

Another term for grape variety.

Downy mildew

Fungal vine disease.

Dryness

A wine that has completed fermentation and has less than 7.5 grams per litre of dissolved sugar remaining is said to have fermented to dryness.

Ethyl alcohol

Ethanol is the primary alcohol in an alcoholic beverage.

Fan leaf

A viral vine disease.

Fermentation

The transformation of sugar into alcohol through the action of yeasts.

Filtration

The removal of solid particles from the juice or wine.

Fining

A clarification technique where a fining agent such as egg white or bentonite is used to aid in the flocculation of particulate matter in the wine.

Flor

A special yeast used to make sherry. This yeast functions with full contact with oxygen and can ferment to higher than 15 per cent alcohol.

Free-run

Juice or wine which flows without pressing.

Fruit set

After flowering the fertilised flowers are "set" to form berries.

Grafting

The insertion of a section, scion, of one variety into another. Genetic compatibility is important.

Hectare

An area of land totalling 10,000 square meters or 2.47 acres.

Hybrid

Grape variety bred from number of different species.

Inert gas

A gas which does not react with the juice or wine. Carbon dioxide or nitrogen are commonly used to fill the head space in tanks and bottles to avoid oxidation.

Lactic acid

A single carboxyl acid produced during malolactic fermentation.

Leaf roll

A viral disease in grape vines.

Lees

Solid waste at the bottom of the ferment, primarily composed of dead yeast cells and grape matter.

Liqueur d' expedition

Liqueur added to top up disgorged wine.

Malic acid

A double carboxylic acid which adds a sharpness to wine. Undesirable in high concentrations it is often reduced through malolactic fermentation to lactic acid.

Malolactic fermentation

Lactic acid bacteria are introduced into the wine. These bacteria convert the harsh malic acid to the softer-tasting lactic acid. A more supple wine can result. This is not fermentation.

Mercaptans

Yeast reacting with lees causing a mousey smell.

Must

Grapes, seeds, skins and juice resulting from crushing grapes.

Noble rot

Highly prized form of the fungal disease Botrytis. Affected grapes will shrivel concentrating sugars resulting in delicious sweet wines.

Oak

A fine-grained timber traditionally used to make barrels for the fermentation and ageing of wine. American oak adds softness to the wine whereas French oak is more robust adding greater body and complexity.

Oechsle

The German measure for the sugar concentration in grape juice or wine.

Oenology

The science of winemaking.

Oxidation

Juice or wine can be adversely affected by contact with oxygen. Oxidation can result in premature ageing of a wine while fruit qualities are preserved in wines with little oxygen contact.

Oxygen

A gas vital for the growth of yeast cells. A small amount of oxygen is important at the start of fermentation. Too high a concentration of oxygen will lead to oxidation of the wine causing a loss of colour, flavour and aroma.

pH

A measure of the concentration of acidity. pH ranges from 1 to 14 with the numbers 1 to 7 being more acidic. Water is neutral at pH 7 and wines are generally between pH 3 - 4.

Phenolics

Alarge group of compounds found mainly in the skins and seeds of the grape. They include the flavonoids, anthocyanins and tannins. During the ageing process of wines many of these are precipitated out. Evidence suggests that red wine will offer greater protection against heart disease than white wine due to its’ higher concentration of phenolics.

Phylloxera

An American vine root pest, present in most countries, which can cause complete vineyard loss. American rootstocks are used for their resistance in affected areas or as an insurance against possible outbreaks.

Potential alcohol

The alcoholic concentration that could be produced if all the sugars present were converted to alcohol.

Powdery mildew

A fungal vine disease common to cooler climates which can lead to crop losses.

Precipitate

When a dissolved substance can no longer stay dissolved and leaves the solution as a solid it is said to precipitate, to leave the solution.

Pressing

White grapes are pressed to release their juice only and not to break the seeds. Red or black grapes are pressed after fermentation to release more of the juice, colour and astringent qualities.

Pruning

Cutting the vine to improve its shape and balance. The level of pruning can affect a vine's vigour and the quality of its yield.

Pulp

The flesh of the grape containing water, sugars and acids. The flesh of most grapes, whether red or white, is clear.

Racking

Transfer of wine from one container to another. The operation must be conducted to minimise the contact with oxygen.

Remuage

The entire process of riddling of the bottles, in Champagne production, to shake the yeast lees to the neck of the bottle for removal.

Residual sugar

Unfermented sugar left in the wine. A dry wine in Australia is defined as having less than 7.5 grams per litre of reducing sugar.

Root stock

Root system to which a grape variety is grafted.

Scion

Grape variety grafted to the rootstock.

Skin

Essential part of red winemaking as it contains pigments, flavonoids and tannins.

Skin contact

Continual and deliberate contact of the skins with the juice during the winemaking.

Sorbic acid

Used to kill yeasts and moulds but can produce the undesirable odour of crushed geranium.

Stabilisation

Processes used to stop the wine from deteriorating.

Sulphur dioxide

Used since Roman times to preserve, disinfect and reduce oxidation in wines.

Tannins

Astringent phenolics. A balanced wine will have soft tannins and give a full-mouth feel.

Tartaric acid

A food acid and a good preservative.

Triage

The sorting of the grapes.

Ullage

The headspace between wine and the top of a container. This is kept to a minimum to avoid oxidation.

Vigour

A vine's growth rate.

Vinifera

Vine species of European origin.

Vintage

The year in which a crop is picked. It can also refer to the harvest itself.

Vitis

The vine genus.

Yeast

A micro-organism of the fungus family. In fermentation of grapes yeast produces primarily ethanol and small quantities of higher alcohols and esters that give a wine its individual character.