The Fascinating Veraison in the Vine Cycle
08 Jul 2024 / Viticulture
In the world of viticulture, each phase of the vine cycle plays a crucial role in the maturation of grapes and, consequently, in the quality of the wine produced. Among these phases, one of the most visually captivating and biologically significant is veraison, known as "pintor" in French. This magical moment marks the transition of grapes from a vegetative growth state to the beginning of their maturation.
What is Veraison?
During the veraison phase, which typically occurs between July and August in the Northern Hemisphere, green grapes begin to change color. In red grape varieties, this change is more noticeable, shifting from green to shades of purple, red, and blue. In white grapes, the change is less intense, turning into a yellowish or golden hue.
The Biological Importance of Veraison
Veraison is a clear indicator that the vine is entering the grape maturation phase. This process involves a series of physiological and biochemical changes:
1 - Color Change: Chlorophyll in the grapes starts to break down, revealing other pigments such as carotenoids in white grapes and anthocyanins in red grapes.
2 - Increase in Sugar: Grapes begin to accumulate sugars, primarily in the form of glucose and fructose, as starch in the leaves is converted and transported to the fruit.
3 - Decrease in Acidity: During veraison, the acidity of the grapes, predominantly malic acid, begins to decrease, balancing out with the increase in sugars.
4 - Increase in Aromatic and Phenolic Compounds: Grapes start to develop compounds that will be essential for the aromas and flavors of the final wine.
1 - Color Change: Chlorophyll in the grapes starts to break down, revealing other pigments such as carotenoids in white grapes and anthocyanins in red grapes.
2 - Increase in Sugar: Grapes begin to accumulate sugars, primarily in the form of glucose and fructose, as starch in the leaves is converted and transported to the fruit.
3 - Decrease in Acidity: During veraison, the acidity of the grapes, predominantly malic acid, begins to decrease, balancing out with the increase in sugars.
4 - Increase in Aromatic and Phenolic Compounds: Grapes start to develop compounds that will be essential for the aromas and flavors of the final wine.
Factors Influencing Veraison
Several factors can influence the timing and duration of veraison:
- Climate and Weather Conditions: Warm temperatures and adequate humidity can accelerate veraison, while adverse weather conditions such as extreme drought or cold temperatures can delay it.
- Viticultural Practices: Vine management practices, including pruning, irrigation, and bunch thinning (controlling the number of bunches per vine), can also impact the timing and uniformity of veraison.
- Grape Variety: Different grape varieties experience veraison at different times. For example, the Loureiro variety generally goes through veraison later than Alvarinho.
- Climate and Weather Conditions: Warm temperatures and adequate humidity can accelerate veraison, while adverse weather conditions such as extreme drought or cold temperatures can delay it.
- Viticultural Practices: Vine management practices, including pruning, irrigation, and bunch thinning (controlling the number of bunches per vine), can also impact the timing and uniformity of veraison.
- Grape Variety: Different grape varieties experience veraison at different times. For example, the Loureiro variety generally goes through veraison later than Alvarinho.
The Significance of Veraison
For the viticulture team, veraison is a crucial time for observation and decision-making. It is the moment to adjust vine management practices to ensure that the grapes reach the desired level of ripeness. Uniformity in veraison can indicate good potential for the harvest, while significant variation between bunches may require additional interventions.
Moreover, veraison is a period when winemakers start planning the harvest, monitoring the development of sugar and acidity to determine the optimal time to pick the grapes, ensuring the best possible balance and quality.
The Reward of a Year’s Hard Work
Veraison is one of the most exciting phases in the annual vine cycle, marking the transition of grapes towards maturation and directly influencing the quality of the wine to be produced. For wine enthusiasts, understanding this process adds an extra layer of appreciation and admiration for the hard work and science behind each bottle. For winemakers, it is a sign that the reward of a year’s hard work is nearing, promising wines that capture the essence of the terroir and the vintage year.
Written by Aveleda