| Primary Fermentation: The Basics |
The following excerpt is from :
THE HOME WINEMAKERS MANUAL
by Lum Eisenman
Chapter 12 PRIMARY FERMENTATION
For more Lum's complete manual, please click on the following link: The Home Winemakers Manual
"Practically all red grapes have clear, colorless juice. The red pigment is in the grape skins. Red wine is made by fermenting the juice, pulp, and skins together, and during fermentation, the red color is extracted from the skins. After several days of fermentation, the new red wine is pressed, and the liquid is separated from the solids. Besides color, many other materials are extracted from the skins during fermentation, and these materials produce the slight bitterness and astringency typical of red wine.
White and blush wines are produced differently. These wines are made by crushing and then pressing the crushed grapes. The liquid is separated from the solids before fermentation is started. White and blush wines are made by fermenting clear juice. Almost no skin contact occurs, and only small amounts of color, bitterness or astringency are extracted from the skins.
White wine can be made from red grapes if the contact between the juice and the skins is limited. French Champagne is made from Pinot Noir grapes, and Pinot Noir is a red grape. White Zinfandel and all blush wines are considered white wines because the juice is separated from the solids before fermentation. Rose wines, on the other hand, are considered red wines because they are fermented with the juice and the skins in contact for a short time. Winemakers use the terms "white" and "red" in two different ways. Besides describing wine color, these terms are also used to indicate the way wine is fermented.
White wines are different from red wines. White wines contain less phenolic material than red wines, and consumers can tell the difference even when the wines are tasted in complete darkness. White wines lack the slight bitterness and the astringency of red wines because the phenolic content is lower.
Quality red wine can be made with rudimentary equipment, but high quality white table wine is much more difficult to make with simple equipment. White wine oxidizes easily, and the effects of oxidation are more apparent. Any off-odors or off-tastes are very apparent in white or blush wines. More and better winemaking equipment is needed to make high quality white table wine, and home winemakers must be prepared to expend more time and effort. "