While there are numerous different styles of wine - single grape variety, blends, sparkling and sweet to name but a few - it’s fair to say that all wine falls into one of three general color categories - red, white or rosé. What’s more, while there are thousands of different grape varieties used to make wine, it is also true that all of these varieties fall into the same three color categories - red, white and rosé.
Yet, when it comes to making wine of the corresponding color, it’s not quite as simple as red grapes produce red wine, white grapes produce white wine and so on. In fact, of the three grape varieties used in the production of Champagne, two of the permitted grape varietals used are actually red and not white.
What is Wine?
To understand how it can be that some red grapes produce white wines, we must look at the process of winemaking. Before doing so, however, we should define what wine actually is:
"Wine is as an alcoholic beverage made from the fermented juice of grapes, where the reaction of sugar and yeast produces alcohol."
While both sugar and yeast occur naturally inside and on the surface of grapes, there are special instances where one of the two, or indeed both, can be added. Besides this however, the only other ingredient that is ever added to wine is Sulphur Dioxide - for antioxidant and preservative purposes.
What Gives a Wine its Color?
The color of wine is always completely natural and comes 100% from the same grapes that give the grape juice. More specifically, it is the skin of these grapes that contains the pigment that gives wine its color. Grape juice, or "must" as it is technically known, is actually colorless.
During the winemaking process (vinification), after grapes have been harvested and sorted, there are two factors that define the color of the resulting wine - particularly reds.
The first is a process called maceration and is a light pressing of grapes to release initial must. The must then remains in contact with the skin and body of the grapes for a time ranging anywhere between a few hours and a few weeks - depending on the grape variety used and desired style of wine. It is at this stage where all red wine develops its color.
Red and White Wine & their Color
The intensity of the color of a red wine varies depending on the amount of time in which the must is in contact with the skins. The pigment and amount of pigment contained within the skin of the grapes has a big effect on the final color of a wine.
Thicker skinned red grapes, such as Cabernet Sauvignon and Malbec, contain a high amount of pigment and produce opaque wines of a deep red color. Thinner skinned varieties such as Pinot Noir contain less pigment and thus produce lighter, translucent red wines.
The skin of grapes also contains tannins. Grapes with thicker skins produce much fuller bodied wines - hence why a Cabernet Sauvignon not only appears darker and more intense than a Pinot Noir, it also has a heavier mouthfeel.
While all red wines go through the process of maceration, it is not a necessary step in the production of white wine. In cases where white grapes experience maceration, rather than being used to give color, the process is instead utilized to improve primary aromas that will be present in the resulting wine.
After maceration, comes pressing. At this point heavy machinery (modern or antiquated) is used to release as much must as possible. Must from white grapes now comes into contact with skins, though only for an intentionally short period. The tannins within the skin of grapes produce a flavor that is undesirable in white wine in anything other than small quantities. Accordingly, contact time between skin and must is short, and for this reason, white wine is much paler and less intense than it’s red counterpart.
How Rosé Wine gets its Color
There are two methods to make Rosé wine. The first and simplest is by blending white and red wines together. The intensity of the rosé color produced in this instance is determined by the proportions of white and red used.
The second technique, "saignée" as it is known in french, uses only red grape varieties. The maceration process begins as normal, but instead of keeping must in contact with the skins for days or weeks, the grapes are pressed completely after 12-24 hours of contact. The released must is much paler in color, and when fermented, it produces rosé wine.
Champagne and Sparkling Rosé
Pinot Noir and Pinot Meunier are the red grape varietals used in the production of Champagne (amongst other sparkling wines). Even though they are red varieties, in the process of making champagne they are macerated and pressed almost immediately afterwards. This short skin contact time creates the pale-yellow color we associate with Champagne. This type of wine, where red grapes produce a white wine, is described as a blanc de noir (white from black).
Rosé Champagne can be produced using the same two methods as still Rosé. In the instance of making a blend, a small amount of still Pinot Noir is added to a Champagne to give a rosé hue. When the saignée method is used, it tends to be the Pinot Noir grape variety that provides the tinted must for the the eventual sparkling Rosé.
It should be noted, finally, that while red grapes can be used to produce blanc de noir white wines, apart from Champagnes and Sparkling wine, it is not a common practice. As a whole, grapes express themselves much better as wine in the form that corresponds to the color of their skin. Hence why you won’t come across many White Cabernet Sauvignons!