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Saccharomyces cerevisiae
Saccharomyces cerevisiae is a major yeast species, often used to ferment white wines.

Screwcaps
Screwcaps are an alternative to sealing a wine with a cork. The advantage of using screwcaps is that they eliminate wine bottle spoiling because of a faulty cork. One disadvantage of using screwcaps is that they eliminate the romantic bottle opening procedure. The jury is still out on their ability to conserve a fine wine for decades. In the meantime, I don't recall drinking an Italian wine from a bottle topped with a screwcap.
Sediment
Sediment consists of small, usually colored particles, that settle to the bottom as the wine ages. While sediment is harmless, it is often removed by decanting to improve the wine’s appearance.
Seed
Of course you know what a grape seed is. Did you know that a typical grape berry consists of about 5% seeds by weight and that grape seeds are a major source of tannins?
Settling
Settling is the precipitation (sinking to the bottom) of solid matter in wine.
Skin
A grape skin protects the pulp. It contains tannins, pigments, and other compounds. At harvest time, naturally occurring yeasts are found on the skins.
Specific gravity
Specific gravity is the density of a substance, such as the fermenting must, relative to the density of water.
Stuck fermentation
Stuck fermenation is when fermentation stops before all the sugar has been converted to alcohol. It is often an unfortunate occurrence. A common reason is when the fermentation overheats, reaching temperatures of 95°F (35°C) or more.
Sugar
Sugar is a group of sweet organic compounds found in many foods including grapes. In the process known as fermentation, yeasts transform sugar into alcohol and carbon dioxide.
Sulfite
A sulfite is a naturally occurring form of sulfur produced by fermentation. In the United States wine labels must indicate "contains sulfites" when the wine contains more than 10 parts per million.
Sulfur
Sulfur is a chemical element often used in winemaking, either in its pure state, or combined with oxygen in the compound sulphur dioxide. These two chemicals are widely used to kill oidium in the vineyard, in the winery as a disinfectant, and in the must and bottled wines to kill bacteria. They also may be used to terminate fermentation. While sulfur and sulfur compounds exist in nature, their use should be limited.
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