Introduction
Zinfandel is a variety of red wine grape grown primarily in California. The color of Zinfandel grapes can range from light pink to deep purple-black. The exact shade depends on several factors, including the grape’s ripeness level, skin thickness, and exposure to sunlight. While Zinfandel is considered a red wine grape, its color is not as uniformly dark as other red varieties like Cabernet Sauvignon or Merlot. Nonetheless, Zinfandel grapes and the wines made from them are classified as red, not white.
Typical Color Range
At the time of harvest, Zinfandel grapes often display a wide spectrum of colors. On the same vine cluster, you may see grapes that are:
- Pinkish-white
- Ruby red
- Dark purple
This variation occurs because not all the grapes ripen at the same pace. The grapes that mature early turn translucent with a pinkish cast. As they approach peak ripeness, Zinfandel grapes transition to a vivid red color. Fully ripe grapes take on a deep bluish-purple pigment.
Factors Affecting Color
Three main factors influence the final color of Zinfandel grapes:
1. Ripeness Level
The riper the grapes are when picked, the darker their color. Grape skins contain water-soluble pigments called anthocyanins that give red wine grapes their color. Anthocyanins develop in concentration as the grapes ripen. Under-ripe Zinfandel grapes will be lighter in color because they have less pigment in their skins.
2. Skin Thickness
Thicker-skinned grapes produce more intensely colored wines. Zinfandel grape clusters typically have a mix of thin-skinned and thick-skinned berries. The thicker-skinned grapes yield more anthocyanins, creating richer purple shades. Thinner-skinned berries absorb less pigment and appear pinkish.
3. Sun Exposure
Grapes grown in sunny, warm conditions have higher anthocyanin levels. More sun exposure catalyzes the production of these color pigments. Shaded Zinfandel grape clusters will be lighter in hue due to less sun activation of the anthocyanin compounds. Vineyard rows oriented east-west provide optimal sun exposure for grape color development.
Distribution of Color
In a typical, fully-ripe Zinfandel grape cluster, the color distribution is:
- 10-20% pinkish-white grapes
- 20-40% ruby red grapes
- 40-60% deep purple grapes
However, these percentages can shift depending on the factors outlined above. Cooler growing areas and less ripeness usually increase the proportion of lighter grapes. Warmer vineyards and greater ripeness shift the balance towards darker colors. But a mix of pink, red, and purple grapes is the norm for Zinfandel.
Why the Color Range?
Zinfandel’s broad spectrum of ripeness levels and berry colors has both genetic and environmental origins.
Genetic Factors
Zinfandel grapes ripen unevenly due to:
- Uneven budbreak – the vines do not push all their buds at the same time
- Variable berry sizes – some grapes mature quicker than others
- Berry shattering – some berries fall off sooner than others
These tendencies are inherent to Zinfandel and account for the asynchronous development and color distribution.
Environmental Influences
Cooler climate zones delay ripening and anthocyanin formation in Zinfandel grapes. Long, drawn-out ripening seasons also contribute to more variation in grape maturity and color. Vine-growing practices like cluster-thinning and canopy management can help reduce uneven ripening. But Zinfandel will always display a certain color variability.
Significance for Winemaking
Zinfandel’s spectrum of grape colors has winemaking implications. Riper, darker grapes produce more intensely flavored and colored Zinfandel wines. Pink and red grapes yield lighter, milder wines. Blending ratios of light and dark grapes will influence a Zinfandel wine’s style.
Most Zinfandel producers prefer to harvest at peak ripeness when color intensity is greatest. Cooler climate regions may opt for earlier picking to maintain acidity. With berry shattering, later harvest runs the risk of losing many grapes. Finding the optimal balance point is an art.
During winemaking, brief skin contact favors light Zinfandel wines. Prolonged maceration brings out dark fruit and tannin character from the fully ripe grapes. Barrel aging also deepens Zinfandel’s color through anthocyanin reactions with oak compounds. Blending choices ultimately determine the wine’s color depth.
Typical Wine Color
Despite the diverse grape colors, most Zinfandel wines display a fairly uniform ruby-garnet hue. This is achieved by:
- Blending lighter and darker grapes
- Letting the juice macerate with the grape skins
- Maturing the wine in oak barrels
These winemaking techniques balance out the grape color variability. They produce richly colored Zinfandel wines that exemplify the varietal character.
A typical Zinfandel wine has color attributes such as:
- Medium ruby-garnet depth
- Moderate opacity at the core grading to a transparent rim
- Vibrant purple and crimson highlights
Lighter styles may tend towards a bright ruby color. Inky opaque purple-black is also possible for intensely extracted Zinfandels. But most lie within the medium intensity range.
Pink Zinfandels
There are also white and pink-colored Zinfandel wines. These are produced with minimal skin contact. The grapes are pressed immediately after crushing, Yielding little color extraction. These “White Zinfandels” became popular in the 1980s and have a light pink coral color. They showcase Zinfandel’s fresh, fruity side as opposed to its bold spice and tannin personality.
Conclusion
Zinfandel grapes display a diverse color range from pink to purple. This variation comes from uneven ripening influenced by the grape’s genetics and growing environment. Winemaking techniques can compensate for the diversity. They produce characteristic medium-bodied garnet-ruby Zinfandels. The grapes’ color directly impacts the color of the resulting wine. But Zinfandel’s richness and complexity arise from the mix of light and dark berries. Their synergistic blending creates the quintessential Zinfandel profile.
