If we look at the newborn babies, we realize the eyes of a dull and indefinite color, so it happens to everyone and it happened to us when we were babies! In fact our irises are also composed of melatonin, a substance that develops only with the light. So that, to know the color of a baby eye, we should wait wait at least one year. It happens with many other species of animals: even our puppy cats and dogs!
On August, if you visit a vineyard during our Wine tasting tour, you quickly will find a very similar phenomenon: observing the vines, you will see the bunches, while being compact, have the grapes of undefined colors, all different: acid green and brilliant, other pink, others red, some already blacks.
This natural phenomenon, in italian is called ”invaiatura”, in english and french “veraison”, that means, it is going to be dark in color.
When the fruit is not ripe yet its skin is thick and contains the pulp of the fruit still young, full of chlorophyll. Gradually the sun, warm temperatures, the moisture, but also the cool of the night, they all do their job, so the skin gets thin and chlorophyll gives way to other substances, especially sugar and yeast. The Botany and Chemistry have established a link between the transformation of chlorophyll in sugar and some colorful substances that prevail over chlorophyll making the grapes change color: they are called “carotenoids” and “anthocyanins”. The first give to the fruits all shades from golden yellow to orange, seconds give the red, blue and black. The colors that you see on the bunch are the sentinels of what happens “inside” the fruit: the more yellow or red or black the grapes, the sweetest and richest their taste.
In fact, it is from this moment on that the grapes in the vineyard will be closely monitored by the winemakers of the winery, because the right color grade and therefore the ripeness will cause the harvest to start: the most important event of the year for the wine!
For Italian red wines such as Chianti and the Super Tuscans, where the high sugar content is crucial, the harvest will be well after the start of veraison, while for lightervwhite wines it will be just after the veraison that the harvest will begin.