It is not needed for table wines but is used for sweet and sparkling wines. Starter - A strongly fermenting yeast culture used to start fermentation in a larger volume of must. Sterilants - Chemicals used to inhibit wild yeasts and spoilage bacteria in musts or on bottles and equipment. May be red or white. Tannin - Astringent substance found in grape pops and stems, and in oak barrels.
Small quantities improve flavor and keeping qualities of wine.
Essential for clearing wine, since organic findings will not work without tannin. Must be added if deficient in wine ingredients. Tartaric Acid - The major acid found in grapes. Thief - The wine thief is a glass tube used to withdraw samples of wine from barrels or carboys for checking clarity and flavor. The amount of fixed and volatile acids in a must or wine, usually expressed in terms of citric or tartaric acid.