The Wine Mine Blagging Toolkit - 5 wine nuggets with which to impress your friends...
1. Starting with the basics - the purpose of grapes is to entice birds to eat them and disperse the seeds, thereby propagating the grape vine. But they don't want to be eaten too early, which is why when unripe they are green (camouflage) and have high levels of tannins and acids (not tasty), turning an appetising red/purple-black when ripe. This colour-change process is known as
veraison and is an indicator of chemical ripening within the grape. (Before you ask "what about yellow grapes", these have been shown to be the result of a mutation in the gene regulating pigment.)
2. Without wanting to get too technical, there are two separate, although related, types of ripeness in grapes - phenolic (or physiological) ripeness and sugar ripeness.
3. In a nutshell, phenolic ripeness has to do with changes in the tannins in the seeds, skins and stems and is influenced primarily by "hang time", the amount of time the grape is left on the vine. Sugar ripeness involves the breakdown of acids and the increase in sugar levels and has more to do with the amount of sunlight and warmth which the grape has experienced (which obviously varies from vintage to vintage).
4. Depending on climate, growers will harvest according to phenolic or sugar ripeness (depending on which tends to occur first). In warm regions, phenolic ripeness occurs after sugar ripeness, meaning it is farily easy to produce wines with high levels of sugar (and therefore potential alcohol), but the challenge is to ensure phenolic ripeness is not delayed so long that the wines become seriously alcoholic. By the same token, picking before phenolic ripeness is achieved to avoid excessive alcohol will leave a bitter green taste.
5. Some new world producers tend to err on the side of over-ripeness ("excessive hang-time"), rather than risk green, under-developed wines. This can produce sweet, sugary wines which are easy on the undemanding palate but have undesirable side effects such as high levels of alcohol and the so-called "dead fruit" phenomenon.
The first French grapes of the year were picked yesterday in Rousillon, marking the start of the 2008 northern hemisphere harvest. Domaine Cazes, 2km north of Perpignan, is the largest organic and biodynamic producer in France. It began picking for its white vin de pays, according to the local wine body, the Conseil Interprofessionel des Vins du Roussillon. It is about a week earlier than last year's harvest.
