Color is the key classification criterion for different wine types. Based on what color of the wine, we can distinguish the following types — red, rose, yellow, orange, and white wine.

But, in reality, color is more than a classifier. Different wine colors and their hue and intensity can help determine wine’s essential properties, like mouthfeel and maturity. In this article, we will identify the ten key factors that influence red wine color and reveal the secrets behind certain red wine hues.

Pouring red wine

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Why look at the color of wine?

Ever wonder why wine tasters look closely at wine color?

Observing the wine’s color can give you a general first impression of what you’re about to taste. Color helps us to understand certain features of the wine, like tannin levels, sweetness, and acidity that influence red wine food pairings. Moreover, wine’s color allows us to spot any undesirable changes in the wine. The subsequent stages confirm these assumptions. When observing wine color variations, professional tasters can identify the grape varieties, the terroir, and the production process.

A variety of red wine colors

If you look at a wine color chart, you’ll see a stunning variety of over 40 shades of red that differ in brightness, tonality, and intensity of the color. To get a more accurate impression of the red wine color hue, look at the wine under natural light conditions and over a white background.  

White wine colors can range from pale (Pinot Blanc) to bright yellow (Sauternes) and rich gold (Chardonnay). The colors of rose wines vary from pale salmon (Provence Rose) to magenta. Red wine colors range from light ruby to dark red or burgundy. 

Evaluating the color can help you assume what type of red wine is in the glass before you. For example, the Pinot Noir color is closer to light ruby, while Carignan and Cabernet Franc tend to have a more intense ruby hue. Zinfandel and Tempranillo wines usually have a garnet hue, Bordeaux Blend and Malbec — a dark purple hue, while Petit Verdot and Petite Sirah are closer to burgundy in their color. 

While the hue and intensity of the wine color can give you specific insights into what type of red wine you will taste, don’t forget to add the brightness of the color to your visual analysis. Brightness may indicate high acidity, making the wine lively and refreshing and giving you the first impression of what you are about to taste.

These are, for the most part, the basic assumptions we can make when looking at the hue of a wine. However, in reality, everything is somewhat more complicated, and various external factors play a role — co-pigmentation, the addition of sulfur dioxide, and others. We will talk about them a bit later, so keep on reading!

glass of red wine

The main factors that determine red wine color

So, what makes red wine red? For the most part, anthocyanin gives the wine red color. Still, many factors influence the color and its intensity, tonality, and brightness. 

Let’s outline the key factors that determine the color of red wine.

1. Anthocyanins

Anthocyanins are an extensive group of plant pigments that color flowers, fruits, and other organs in various shades from pink to black violet. These phenolic compounds are present in red grapes, fruits, plums, blueberries, and cherries. You can also observe them in orchids and hydrangeas.

While in most red grape varieties, anthocyanins are present only in the skins of the berries, the juice of certain types (for example, Tenturier) also contains anthocyanins.

Traditionally, we believed that anthocyanins are absent in white grapes. However, recent studies have discovered that white grapes also contain anthocyanins. Still, their concentration is way smaller than in red grape varieties.

Red wine producers’ main challenge is extracting anthocyanins from grape skins into must and wine material and preserving the color. Unfortunately, as red wine ages, the content of anthocyanins decreases because of their oxidative condensation and polymerization.

2. PH levels

There are nearly 20 different types of anthocyanins contained in red grapes that vary in their PH levels. Therefore, a PH level is another factor that determines what color from the wine color chart the wine will have.  

The intense red color of wine tells us about a low pH level, which also means higher acidity. Wines with rich purple hues usually have medium pH levels (3.4–3.6). Dark wine colors with a more blueish tint are typical for wines with higher pH levels (over 3.6), higher tannin levels, and lower acidity levels.

For example, Sangiovese is a bright red wine with high acidity, while Malbec, a highly colored red wine that often has a blue tint on the rim of the glass, has a lower acidity level.

3. Grape skins and the color of pulps

As mentioned above, color pigments have a significant impact on the color of the wine. Now, let’s dive deeper and see how the content of coloring pigments varies among different grape varieties.

There is a direct correlation between the concentration of coloring pigments and the thickness of the skin of the grapes. So, grape varieties with thinner skins have fewer color pigments than grape varieties with thicker skins. As a result, Cabernet Sauvignon and Merlot are more intense in color than Pinot Noir and Gamay.

Here is a fun fact: unlike grape skins, the grape pulp is usually transparent. That’s why winemakers can produce white wine like Blanc de Noir Champagne from red grape varieties like Pinot Noir grapes. The key here is to avoid any contact between the grape juice and the skins.

4. Terroir and vineyard

The growing environment of the grapes, also referred to as “terroir,” is another determinant of the wine color and taste of red wine. The environmental factors include the climate, soil composition, exposure to sunlight, elevation, and the work done in the vineyard.

A warm climate with sun and rain contribute to growing grape varieties with thicker skins, as a vine protects the fruit against heat. As a result, such grapes will produce red wine with intense color. Hot climates, though, often make the grape skins thinner due to too rapid ripening of grapes.

Calcium-rich soils often make grape skins thick (and thus rich in color pigment). As a result, sandy soils will likely produce thinner-skinned grapes that are less intense in color.

As you probably know, the content of anthocyanins in red grapes depends on the energy of photosynthesis. Therefore, the exposure of grape leaves to sunlight affects the formation rate of anthocyanins and, consequently, the color of grapes. 

When it comes to the grapes ripening, the elevation and steepness of the vineyard matter, a higher elevation combined with a cool climate contributes to growing grape varieties with higher acidity levels, such as Malbec. Growing in Argentinian vineyards 4,000 feet above sea level, the Malbec grape variety features thick skins and deep purple color.

Proper vineyard care also contributes to the protection of the color of red wine. The work in this direction includes preventing grapes from sunburning, monitoring vine hormone balances, and de-leafing early during grape development. In addition, timely de-leafing helps grapes accumulate phenolics to ensure protection from sunburning.

5. Maceration period

Red wine production starts with the maceration period — a process aimed at leaching anthocyanins from crushed grapes, stems, and seeds into the must. During this period, grapes naturally release the phenolic compounds responsible for coloring the wine.

The maceration period is a variable that influences the intensity of the wine’s color. Red wine production involves longer maceration periods than rose or white wine production. With red wine, the optimum maceration time is about eight days, although, in some instances, maceration times can take up to several weeks. Maceration temperatures are also higher with red wines to ensure the extraction of anthocyanins.

6. Fermentation

Along with maceration, red wine production involves such a biological process as the fermentation of sugars. During this process, yeast converts grape sugar to alcohol. An adequately organized fermentation process has a significant impact on the color of the wine produced. 

Including whole-grape clusters, stems, and lees in the fermentation process may reduce the intensity of red wine color. Why is that? Because these inclusions may absorb color molecules. 

The fermentation temperature also matters. With red wine production, the optimal fermentation temperatures for color extraction from the grape skins may range from 68 to 86°F. Higher temperatures make retaining aromatic varieties’ delicate aroma and flavor challenges.

The fermentation time also has an impact on the color intensity. For example, longer fermentation can help produce darker and more concentrated red wine.

Red wine making

7. Winemaking techniques

Red wine producers can apply various winemaking techniques to achieve the best results when extracting color pigments into grape juice. One of them is the cold soak technique (also known as cold maceration) which involves holding crushed grapes at low temperatures ranging from 5 hours to 10 days. As long as cold maceration precedes the fermentation stage(before converting grape sugar to alcohol,) the interaction between grape skins and juice enhances the anthocyanin extraction.

Another technique is extended maceration assuming longer interaction between grape skins and juice. After fermentation, extended maceration gives the wine up to a couple of weeks more to soak on the skins, ensuring the extraction of color pigments to the fullest. This technique also contributes to making tannin molecules less bitter.

8. Sulfur additions

Sulfur dioxide is an additive widely used in winemaking as an antioxidant and an inhibitor of undesirable microbial growth. The amount of SO2 used influences the color of wine and its intensity. Red wines with more sulfur dioxide added tend to have a less intense color. Here is why: sulfur dioxide may bind to other substances, including anthocyanins. Bound anthocyanins are subject to bleaching, resulting in a lighter wine color.

9. Aging

Different wine colors can also characterize different stages of wine maturity. As wine ages, it undergoes chemical auto-oxidation reactions, often causing red wine to darken from red to a more tawny color. Can a winemaker do anything about that?

You might not have known about this, but the type of container used during aging affects the intensity of wine color. For example, keeping wine in stainless steel tanks ensures a reductive oxygen-free environment, which helps preserve the wine’s color, taste, and aroma in the long run. In contrast, keeping red wine in oak barrels creates an oxidative environment, making the wine color paler.

In this regard, assessing the tonality of red wine color can hint at how it has been aging. A bright tonality speaks about a fully mature state, while a gloomy tonality may indicate oxidized wine with lost flavor and aroma. 

For example, when tasting Brunello di Montalcino aged 8-10 years, we see a garnet-red color with orange or brownish tints. The color confirms the type of wine, and the shade ensures the evolution of the wine.

The anthocyanin concentration influences the wine’s aging potential and can indicate which tank or barrel material should be used. A greater anthocyanin concentration results in higher reductive strength of the wine and, consequently, a higher aging potential. Young red wines are often purple, medium-aged red wines tend to be ruby, and mature wines may have a garnet hue.

10. Exposure to oxygen

The exposure of red wine to oxygen has a particular impact on its color, aroma, and taste. With bottled wine, small amounts of oxygen are suitable for proper aging — much smaller than the amounts needed for fermentation. 

How can a winemaker add pre-defined amounts of oxygen into wine bottles? Natural wine corks cope with this task by allowing tiny amounts of oxygen. Synthetic corks that are popular today also work for this purpose, as most of them ensure the required air permeation rate.

red grapes

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Final notes on red wine color

Now that you know what determines the color of wine in your glass, you can start making assumptions about its mouthfeel and maturity while looking at it. Over time, you can even learn to distinguish the different grape varieties used in production by the hue of red wine and determine the style of red wine just by looking at it.

Whether you participate in wine-tasting events or want to have your wine collection, evaluating the wine color will give you a hint about its properties. Color observations can provide insights into how the wine you will taste has been made and maturing. Visualizing the story behind the wine in your glass will bring mindfulness and awareness to your wine-tasting experience.