New to wine? Wanting to know about the process? Confused by the lingo? Look no further than our glossary of winemaking terms.
A Acetaldehyde A product of the oxidation of ethanol. Also a desirable note in Sherry. Acetic acid Generally undesirable in winemaking. Produces vinegar notes in wine. Caused by poor fruit or poor winemaking. Commonly known as Volatile Acidity. Acetobacter A bacteria found in wine that can oxidise ethanol to acetic acid under the presence of oxygen. Commonly used in vinegar production Acidity / Acid Gives acid perception on palate. Acid is produced in grapes, but can also be added in the winery. Aerobic conditions In the presence of oxygen. Alcoholic Fermentation The conversion of sugar to alcohol by yeast. Amphora A ceramic vase, used winemaking in ancient times. Now used by hipsters. Anaerobic The opposite of aerobic. Without the presence of oxygen. Anthocyanin Pigment in grapes that are extracted into wine. Influences colour. Antioxidant Commonly found in grape skins or chemical additions. Prevents must or wine oxidation. Ascorbic acid An antioxidant used to prevent grape must from oxidizing. Assemblage The blending of wine parcels to create a final blend. Autolysis The breakdown of dead yeast cells (or lees). A winemaking technique used to build creaminess, brighten colour, scavenge oxygen.
B Barrel fermented A wine fermented in oak barrels. Barrique A common oak barrel. Generally either 225L or 228L. Baumé Measurement of the sugar concentration in the juice or wine. 1 Baumè equals approximately 18g/L sugar Blanc de Blancs Sparkling wine made exclusively from white (Chardonnay) grapes. Blanc de Noirs Sparkling wine made exclusively from red (Pinot Noir and Pinot Meunier) grapes. Blending The combination of different parcels of wine to make another wine. Bottle Age The length of time that wine has been allowed to age and mature in bottle. Bottle shock Typically seen after bottling and transport. A state of unusual presentation of a wine after it has been knocked around. Bottle variation Differentiation of different bottles from the same batch of wine. Brettanomyces A wine spoilage yeast generally caused by fermentation of sugar left over from fermentation. Commonly produces taints in wine commonly described as barnyard or band-aids. Brut A French term for a very dry Champagne or sparkling wine. Drier than extra dry.
C Cap The layer of skins that forms at the top of a tank during fermentation. Carbonic gas Either produced by fermentation, or added via injecting carbon dioxide into the wine. Gives spritz on the palate. Carbonic maceration A fermentation practice commonly used to enhance fruity, deeply coloured red wines with low tannins. Commonly done by minimising the amount of breakage to berries before fermentation. Casein A fining agent derived from milk. A protein used to remove off odours, bleach colour and clarify white wines. Cellaring Ageing wine in bottle. Cork taint Also known as Trichloroanisole (TCA). It is a wine fault caused by mould growth on corks. Typically aroma of mouldy newspaper, mouldy cellar wet dog or damp cloth.
D Demi-muid A barrel that holds 600L. Generally with 34mm thick staves.
E Egg white fining A protein fining agent. Attacks astringency in wine commonly found in red wines.
F Fatty acids Yeast bi-products responsible for desirable aromas in wine. They include volatile esters and lactones. Fault Unpleasant flavours seen in wine. Typically faults are able to be described with common descriptions. Fermentation When yeast convert sugar into alcohol.
G Gelatine An aggressive protein fining agent typically to remove astringency in wine.
H Hogshead A wine barrel that typically holds 300L Hydrogen sulfide An aroma released by stressed yeast or yeast that have little contact with oxygen. Typically seen as rotten eggs, but can take on aroma of flint and lees.
I Isinglass Used as a fining agent in white wines. Used to remove polyphenols that give astringency. It also helps to remove yeast in suspension and aids settling. A very specific fining agent.
J Juice A sugar medium, prior to alcoholic fermentation.
L Lactic acid Produced in wine after the conversion from Malic acid to Lactic acid from malolactic fermentation. Lees Sediment that occurs during and after yeast fermentation, and consists of dead yeast and other solids. Lees stirring Also known as bâttonage, Lees are stirred up to extract flavour, improve colour and improve other sensory components into the wine and also to avoid reductive conditions that may contribute to various wine faults.
M Maceration The length of time grape skins are in contact with juice during fermentation, this process aids extraction of phenolic compounds including tannins, anthocyanins, and other aromas. Malic acid A naturally occurring grape acid. Typically known for a green apple flavour. It is always converted to lactic acid in red wines for microbiological stability via malolactic fermentation. Malolactic fermentation The conversion of malic acid (hard acid) to lactic acid (soft acid) by bacteria. Mannoprotein Extracted from aging wine on lees for extend periods from yeast cell walls breaking down. Typically improves stability, improves colour and improves mouth feel in wine. Marc Pressed grape skins. Used to make grappa and other spirits. MOG Abbreviation for “Matter Other Than Grapes” commonly seen in machine picked fruit as leaf, petiole, stem, snakes, lizard, bicycles etc,
O Oak Used to add tannin, flavour and texture. Oechsle A measure of must weight Oenology The science of wine and winemaking. Off-dry Describes a wine with residual sugar. Typically seen in Rieslings and Chenin Blanc. Orange wine A hipster wine.
P pH A measure of the acidity. Influences many factors in wine including colour, oxidation potential and biological stability. Phenolic compounds Extracted from skins, seeds and stalks. Can contribute to the colour, texture and flavour in wine. Binds with anthocyans to build long chain phenolic compound conducive to smoother tannin and greater cellaring potential. Polyvinylpolypyrrolidone (PVPP) A synthetic fining agent. Used to remove bitterness and helps to remove/prevent browning. Potential alcohol An approximate alcohol determined by the sugar value. Puncheon A wine barrel typically of 500L.
R Racking Decanting wine/juice off its sediment. Residual sugar Sugar left in wine to add sweetness/balance. Rosé wines Typically made by treating red grapes like white grapes. The pink colour is generally pick up by a small amount of contact with grape skins in the aqueous phase.
S Screwcap Commonly known as “Stelvin” the screwcap is a closure that can be used to seal wine bottles. Skin contact In contact with grape skins either before, during or after fermentation. Still wine Typically known as a table wine Stuck fermentation A fermentation that undesirably stops fermenting sugar. Generally attributed to poor winemaking or diseased grapes. Sulfites Added to most wine as sulphur dioxide. Sulphur dioxide Used as a preservative and antioxidant. Commonly seen on wine labels as preservative 220. Used as an antioxidant and anit-microbial. Sur lie A winemaking practice that involves prolonged aging on the dead yeast cells.
T Tannin Phenolic compounds that give wine a bitter, dry, or puckery feeling in the mouth and can give wine its structure. Tannin also contributes to the preservative/anti-oxidant potential of wine. Commonly derived from the seeds (pips), skins and stalks of grapes. Tartaric acid Naturally occurring acid in the grape. The most commonly added acid to wine/juice Tartrates Crystal deposits precipitated in wine either before of after bottling. It is harmless so don’t stress when you see it. Topping Filling barrels during their maturation period. Wine evaporates and wines should be topped monthly at least. Total acidity The measurable number of total acidity in wine, measured in g/L.
U Ullage Also known as headspace, the unfilled space in a wine bottle, barrel, or tank. Derived from the French ouillage, the terms "ullage space" and "on ullage" are sometimes used, and a bottle or barrel not entirely full may be described as "ullaged". It also refers to the practice of topping off a barrel with extra wine to prevent oxidation.
V Volatile Acidity Seen as a wine fault aroma of vinegar. Can be used as a winemaking technique where the volatile acidity (VA) of a wine is deliberately elevated in order to enhance the fruitiness of wines that are meant to be consumed young. Vanillin An aldehyde found naturally in oak that imparts a vanilla aroma in wine. Varietal A wine made from a single grape variety Véraison French term (now English also) for the onset of ripening of the grape cluster. Vin de paille French for "straw wine", a dried grape wine. Vinegar A sour-tasting, highly acidic, liquid made from the oxidation of ethanol in wine, cider, beer, fermented fruit juice, or nearly any other liquid containing alcohol. Vinification The process of making grape juice into wine. Vin jaune French for "yellow wine", a wine fermented and matured under a yeast film that protects it, similar to the flor in Sherry production. Vinimatic An enclosed fermentation tank with rotating blades that operates similar to a cement mixer with the propose of maximizing extraction during maceration and minimizing the potential for oxidation. Volatile acidity Acids that are detectable on both the nose and the palate. The level of fatty or volatile acids in a wine that are capable of evaporating at low temperatures. Acetic and carbonic acids are the most common volatile acids but butyric, formic and propionic acids can also be found in wine. Excessive amounts of VA are considered a wine fault. Volatile phenols Phenolic compounds found in wine that may contribute to off odours and flavours that are considered wine faults. The most common types of volatile phenols found in wine are ethyl and vinyl phenols. To a limited degree some volatile phenols may contribute pleasing aromas that add to a wine's complexity, such as ethyl-4-guaiacol which imparts a smokey-spicy aroma.
W Wine An alcoholic beverage made from the fermentation of unmodified grape juice. Wine cellar A cool, dark location in which wine is stored, often for the purpose of ageing. Wine fault Undesirable characteristics in wine caused by poor winemaking techniques or storage conditions. Winemaker A person engaged in the occupation of making wine. Wine-press Used to separate the grapes skins from the juice or wine. Winery A building, property, or company that is involved in the production of wine. Wood lactones The various esters that a wine picks up from exposure to new oak. These lactones are responsible for the creamy and coconut aromas and flavours that develop in a wine.
Y YAN Yeast Assailable Nitrogen, a measurement of amino acids and ammonia compounds that can be used by wine yeast during fermentation Yeast A microscopic unicellular fungi responsible for the conversion of sugars in must to alcohol. This process is known as alcoholic fermentation. Yeast enzymes The enzymes within yeast cells that each act as a catalyst for a specific activity during the fermentation process. There are at least 22 known enzymes that are active during fermentation of wine.