Special Sub-Topic: Wine Production Click Here To Play: Wine Production

Wine-making is the production of wine from a selection of grapes and resulting in bottled wine. What is this entire process called?

Vinification. The science of wine-making is known as enology. Wine-making can be divided into either still wine production or sparkling wine production. Wine can be produced from plants or fruit other than grapes. Mead, for example, is a wine concoction made with honey.

The first step in wine production is the harvesting of grapes. When to harvest is determined by a variety of factors, one of which is the sugar level. What is this measurement called (there are other names, but of these four, only one fits)?

Brix. Brix is a measurement of the fraction of sugar contained in the grape. The measuring device used is a saccharimeter and is typically portable. It is used directly at the location of the grapevines. This instrument measures the density of the grape must which indicates grape ripeness and sugar content. Another method used, especially in Europe, is the Oechsle scale.

After the harvest, the grapes are crushed and allowed to ferment. During fermentation, what is the substance that converts the grape juice into alcohol?

Yeast. Yeast converts most of the sugars in the grape juice into ethanol and carbon dioxide. After the primary fermentation, the liquid is transferred from the vat into tanks where most of the sugars are slowly converted into alcohol and the wine begins to clear. The amount of sugar conversion would be at the wine makers discretion depending on how sweet he wants the wine.

Grape quality is affected by variety as well as weather, soil minerals, acidity, time of harvest and pruning methods. What is the combination of these effects known as?

Terroir. Grapes are usually harvested from September to November in the Northern Hemisphere, and from February to March in the Southern Hemisphere. The most common species of of wine grape is Vitis vinifera which include nearly all varieties of European origin.

Pressing is the act of applying pressure to grapes in order to separate juice from the grape skins. Which less common method is also used?

Crushing. When grapes are crushed as opposed to pressed, a considerable amount of juice is immediately released. Typically, this free-run juice is of higher quality than the pressed juice. However, wineries usually use presses as it increases their production.

To make certain types of wines, grapes are put through a crusher and then poured into open fermentation tanks. What is the wine-making term for the traditional stomping of grapes in these tanks?

Pigeage. Once fermentation begins, the grape skins are pushed to the surface by Carbon Dioxide gases. The skins need to be mixed through the liquid daily. This process is done by stomping through the vat, keeping the skins below the surface.

After the wine has fermented, fining agents are used to remove tannins, reduce astringency and remove particles that cloud the wine. What is used as a traditional method for wine fining or clarifying?

Gelatin. Generally, gelatin does not remain in the wine because it reacts with the wine components as it clarifies and forms a sediment which is removed by filtration prior to bottling.

Preservatives are commonly used to prevent bacterial spoilage and oxidation. What is an example of such a preservative?

Sulphur Dioxide. Sulphur Dioxide is added after alcoholic fermentation along with Potassium Sorbate to prevent bacterial growth. This in conjunction with proper hygiene should keep your wine clean.

All production methods for sparkling wines have the purpose of introducing enough gas in the wine to make it "bubbly". Which gas is this?

Carbon Dioxide. Carbon Dioxide is injected into the wine much like the process used in soft drinks which produces big bubbles that dissipate quickly in the glass. This method is usually only used when ease of production and quantity matter the most. To obtain a quality sparkling wine, a secondary fermentation process under pressure is preferred.

The final process is the bottling of the wine. Traditionally, what are the bottles sealed with?

Corks. There are alternative wine closures such as synthetic corks and screwcaps. These are subject to less cork taint and are becoming increasingly popular. Lastly, a capsule is added to the top of the bottle which is heated for a tight seal.