Terminology

Term	Definition
ATF (BATF)	See TTB.
Alcoholic fermentation	The conversion of sugar to alcohol and carbon dioxide through the action of yeast. It is a heat producing reaction.
Amelioration	The addition of sugar and/or water to must or wine. This can also refer to adjusting the acid level.
Aroma	Grape derived odors in wine.
Balance	A term that describes how the parts of a wine blend together so that no one particular flavor or characteristic dominates, but all complement each other.
Body	This refers to the texture and "mouth feel" of a wine, light or heavy.
Bouquet	Odors in wine derived from processing and aging.
Brix	Term that expresses the percent sugar concentration in juice.
Buret	A graduated glass tube with a small aperture and a stopcock delivering measured amounts of liquid, used in acid base titrations.
Cap	Layer of grape solids that float on the surface during red wine fermentation "on the skins".
Carboy	A glass container with a narrow neck that comes in 3, 5 and 7 gallon sizes, used for making wine.
Citric acid	One of the acids found in grapes and wine.
Cold stabilization	Chilling wine before bottling to remove excess potassium bitartrate in order to prevent its precipitation in bottled wine.
Chromatography	An analytical procedure used to determine the levels of malic and lactic acid during malolactic fermentation.
Crushing	Breaking the skin of the berry to release the juice.
Dry	Wine without a noticeable sweet taste.
Enology	The science of winemaking.
Fining	A process to clarify, stabilize and/or modify wine quality by addition of agents such as bentonite clay, egg white, PVPP, gelatin and others.
Flavor	A term to describe the smell and taste of a wine.
Foxy	Musty, earthy flavor characteristics of native American wines made from Vitis labrusca grapes.
Free run	Juice or wine that drains without pressing.
Free SO₂	Sulfur dioxide ions in solution not bound to other chemicals and so are free to prevent oxidation, etc.
French-American hybrid	Hybrids or crosses between American cultivars of grapes and European cultivars of grapes. Also called French Hybrids.
Head space	The air space above wine in a closed container.
Heat stabilization	Removal of heat unstable protein.
Hydrometer	An instrument that measures the specific gravity of a liquid at room temperature. A sacchrometer is a hydrometer that is calibrated to read °Brix or % sugar.
Lactic acid	One of the acids found in grapes and wine.
Lees	Sediment.
Malic acid	One of the acids found in grapes and wine.
Malolactic fermentation	Conversion of malic acid to lactic acid by lactic acid bacteria.
Must	The term for crushed grapes and juice until the end of fermentation.
Nose	The odor of a wine composed of aroma, bouquet and other factors.
Oxidation	A wine disorder resulting from excessive exposure to oxygen. Browning of the wine is a result of oxidation.
pH	Measurement of H+ (hydrogen) ion activity.
Pipette	A narrow tube into which fluid is drawn by suction and retained by closing the upper end. A 5 ml pipette is designed to draw 5 ml liquid at room temperature.
Potassium metabisulfite	A source of sulfur dioxide (58% SO₂) for use in winemaking.
Pomace	Material remaining after pressing the must.
ppm	Parts Per Million. Milligrams/liter = ppm for example. One milligram is 1/1000th of a gram. One liter equals 1,000 milliliters (which in turn is equal to 1,000 milligrams of water by weight).
Punch down	Manually breaking and submerging the cap during red wine fermentation.
Racking	Separating clear wine from sediment or lees during production.
Reducing sugar	Fermenting sugars that will reduce copper upon chemical analysis.
Refractometer	Simple optical instrument that measures the amount a given solution bends light and so determines the amount of soluble solids in solution (sugars) by measuring the amount of bend on the Brix scale (distilled water = 0°Brix).
Residual sugar	Sugar left in the wine after alcoholic fermentation.
Stuck fermentation	Premature cessation of fermentation.
Sucrose	Table sugar added to wine that is not a reducing sugar. It is converted to glucose and fructose by grape and yeast enzymes and by low pH conditions.
Sulfur dioxide	An antiseptic that prevents spoilage and oxidation in wines when the concentration in the juice and wine is managed properly.
Tannins	Compounds in grapes and wine that impart astringent (pucker) and/or bitter flavor. Tannins are extracted from grape skins, seeds and stems. Oak tannins are extracted from aging in oak barrels or from oak additives.
Tartaric acid	The primary acid found in grapes.
Titratable acidity	Acid content determined by titrating must/wine with sodium hydroxide and following a formula. The term is commonly expressed as grams of tartaric acid per 100 ml or % total acid.
TTB	United States Alcohol and Tobacco Tax and Trade Bureau. The Federal agency that regulates the production and sale of alcoholic beverages in the U.S.A.
Volatile acidity	Acetic acid content of a wine that is used as an indicator of spoilage. Vinegar.
Vitis aestivalis	A native American grape cultivar or variety.
Vitis labrusca	A native American grape cultivar or variety, with "foxy" character.
Vitis vinifera	A European grape cultivar or variety.
Wine library	A collection of wines where the location of the bottle in storage is cross referenced to information about the particular wine.
Wine thief	A hollow tube with tapered openings at both ends, that is used to extract samples of wine from larger containers for analysis.
Yeast	Fungi that can carry out alcoholic fermentation.