Although most people prefer to call wine wine, the truth is that wine is a generic term for wine and does not necessarily refer specifically to wine. There are many ways to classify wine. Based on color, wine can be classified as red or white. But do you know why red wine is red and white wine is white? What is the difference between them?
I. Why is red wine red and white wine white?
1、Where does the color of wine come from?
I believe many people know that the color of wine comes mainly from the grape skins. In fact! According to the color, wine grapes can also be divided into red and white, which can make a difference in the corresponding color of the wine. It is worth mentioning that white wine can also be made from red grapes.
2. What gives grape skins a certain color?
Since the color of wine comes from the skins, where does the color of the skins come from?
(1) White wines
Like lemons and other fruits, grapes contain large amounts of light flavonoids, which include a variety of chemicals that can be yellow, beige or white in color. White wine derives its color from these substances, so it is often pale green, yellow, straw, or even a common light gray color.
(2) Red wine
This wine has a purplish red color and is extracted from the skins of the grapes used to make it.
Red grape varieties usually contain more anthocyanins, which are redder or more purple. In addition to grapes, other vegetables and fruits such as red cabbage, beetroot, eggplant and berries also contain this anthocyanin.
The pigments in grapes are usually found in the skins, so the flesh is mostly light or even colorless, which is why red grapes can be used to make white wine. For example, Blanc de noirs is a white wine made from the red grape varieties Pinot Noir or Meunier. For red wines, successful winemaking must effectively extract the pigments from the skins to produce the desired color and desired style.
Only a few grapes have color in their flesh. They are often referred to as “contaminants” and can often produce a more colorful juice. The most famous dyed grape is Alicante-Buschert.
3. How is the color of the grapes transferred to the wine?
Since the color of grapes mainly exists in the skins, and the skins do not hold the wine, how is the color of grapes transferred to the wine? In fact, the grape juice absorbs the pigments during the maceration of the skins, thus giving the wine a certain color. Of course, after the harvest, the winemaker will decide how much pigment to extract based on the style he wants, and the process of pigment extraction is the key to the different colors of red and white wines.
(1) White Wines
In fact, white wine almost never extracts color from the skin. After harvest, the juice is usually crushed and separated from the skins before fermentation, so the color of white wine is roughly the same as the color of the flesh.
Of course, there are exceptions to everything. Sometimes white wines are subjected to a short maceration process of a few hours to increase the flavor intensity and color intensity.
(2) Red wines
Wine is fermented with the skins, so the flesh and skins are usually placed together in fermentation tanks for skin maceration and color extraction, and the fermentation of the must is also done together.
Of course, it is not necessary to ferment the wine in the skins. Some people choose to extract the pigments quickly before fermentation, such as by heating the must at a high temperature to facilitate the extraction of the pigments.
What are the differences between red and white wine making?
Obviously, the difference between red and white wines is not only in color. So, what are the differences between their respective winemaking processes?
1. Tannins from the skin of the fruit
The tannin content of a wine is also a key point of differentiation between red and white wines: in general, red wines have a higher tannin content than white wines, so they taste drier and more astringent.
(1) White wines
Because some white wines undergo a short maceration process during the winemaking process, some white wines contain a small amount of tannins, which gives the wine a bitter and astringent taste (aftertaste). Of course, the exact amount varies depending on the grape variety. For example, Pinot Grigio contains more tannins than regular white grape varieties, and sometimes Viognier and Riesling can have a dry aftertaste.
(2) Red wines
The tannins in red wines come mainly from the winemaking grapes: compared to white varieties, red grapes contain not only anthocyanins, but also more tannins. Tannins are also extracted and dissolved in the must during the skin maceration process, which gives the wine its unique tannin texture.
2. The influence of oak barrels
Oak barrels are more commonly used for maturation and aging of red wines. They can bring three important things to the wine.
(1) Flavor
Oak barrels are usually toasted to some degree, so they bring more hazelnut, vanilla, coffee, smoke and other flavors to the wine.
White wines are inherently light in flavor, and too much oak can cause dryness. For this reason, most white wines are not aged in oak barrels, although there are exceptions.
(2) Tannins
Like the skins, oak barrels contain a certain amount of tannins that dissolve in the wine as it ages. In addition, the tannins in oak barrels are better than those in the skins, and can help to further soften the tannins in the wine.
White wines contain fewer tannins and therefore do not need to be softened by this operation. Of course, there are exceptions for Chardonnay. Usually, they become richer when they are colored by the tannins on the oak barrels.
(3) Oxygen
Oak barrels allow small amounts of air to enter and gradually react with the other components of the wine, thus promoting the oxidation of red wines to soften the taste.
White wines are very sensitive to oxygen, so if a white wine like Chardonnay needs oak aging, it will be for a shorter period of time than a red wine.
Are red wines more durable than white wines?
Because of the difference in the composition of red wines and white wines, their aging potential is also different. Generally speaking, the polyphenols in wine, such as tannins and anthocyanins, have strong antioxidant properties, which means that the grapes can grow slowly without worrying about excessive oxidation. Therefore, on balance, red wines are more durable than white wines.
However, not all red wines have to have greater aging potential, as some fine white wines can sometimes be stored longer than red wines, such as German Sauternes or expensive sweet white wines with decay, which often have great aging potential.
