We have seen in a previous article the importance for a winemaker to harvest, especially in the production of quality red wines, grapes that have a optimal polyphenolic maturity, evaluating the peel and pips very well.
But why can even 24 hours be important?
At the biochemical level, many synthesis and polymerization reactions take place which from day to day allow us to have small but important changes.
What does polyphenolic ripening depend on?
Why are red grapes harvested when average temperatures are lower?
Why have we heard of thermal shock?
Let's see if these are all important factors for the winemaker.
I have tried to summarize all the factors that play a fundamental role in polyphenolic quality of our grapes and consequently of our wine.
Depend on:
• Correct mineral nutrition
• Limited vegetative vigor
• Grape weight of the low strain
• Respect the leaf surface ratio of 1-1.5 m2 per kg of grapes
• Terroir and obviously form of breeding
• Average daily temperature close to 20 ° during the ripening process (ie the period from veraison to harvest)
• Minimum day / night temperature difference of 8/10 ° C or higher
• Water stress
Nature plays a fundamental role and the vintage of a wine is the daughter of many factors.
And we're only talking about polyphenols.
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