© Microsoft Corporation. All Rights Reserved.

Wine Production

Although wine makers use many different techniques to produce wines with unique characteristics, there are six basic steps involved in most wine production. To make red wine, grapes are passed through a mechanical destemmer-crusher (1) to remove the stems and release the juice. The juice, stems, and skins, now called must, is transferred to a fermentation tank (2), where it remains for up to 14 days while yeasts slowly convert the grape sugar to alcohol. The juice, now considered wine, is separated from the skins and stems by passing it through a press (3). The wine is pumped into barrels (4), often made of oak, where it continues to ferment and develop in a process known as aging. During aging, residue settles to the bottom of the barrel and forms a sediment called the lees. Wine makers may separate the wine from the lees in a process called racking, transferring the wine to clean casks (5). Finally, the wine is mechanically bottled (6), corked, and packaged for distribution. In white wine production the grapes are separated from the skins and stems before fermentation. The grapes are passed through a destemmer-crusher (A), and the must is immediately passed through a press (B) that applies pressure to separate the juice from the skins and stems. The remaining steps, fermentation (C), aging (D), racking (E), and bottling (F), are similar to those of red wine production.