How the grapes are pruned and trained on the trellises, how much water and sun the vines receive, how much spraying is done to combat pests and diseases, and how many bunches of grapes are allowed to mature on each vine all contribute to the quality of the grapes at picking, an essential prerequisite to good wine.
The point at which the grapes are picked is equally critical. If you are looking for maximum natural sugar content, as in the finest sweet German wines, you pick as late as possible. If you want high acidity, as in many of the Loire whites, you pick early or plant the vines in areas which get less sunshine. In South Africa, and now many other countries, the grapes are picked at night when it is cooler and the fruit fresher, with more trapped flavour.
The speed and method of the grapes’ delivery to the winery is also important. In some countries, where the grapes have to be delivered to central wineries, it is not unusual to see lorries queueing in the blazing sunshine for many hours before they can dump their loads. By the time the lorries unload, the juice has started to ferment and the finished product will be dreadful. The best wines are often produced from grapes which are picked in small quantities into small containers and handled carefully.
Wineries can vary enormously from country to country. In peasant areas of France, Italy and Spain many wineries have changed little in decades and neither have the wine-making techniques. In California and Australia you can see some of the most modem wineries in the world. The huge investment that a modem winery involves does not automatically mean it will produce good wines. It does, however, iron out many of the problems and allows more control over the wine making process, so fewer bad wines should be made.
In the end it comes down to the skill of the wine-maker and, as many of the finest wines from the Rhone and southern Italy prove, you don’t have to have the latest hi-tech wineries to produce some of the world’s greatest wines. When the grapes reach the winery the juice is extracted by putting them into a press, which also separates out the skin, pips, stalks and any stem.
Almost all grape juice is clear, and red wine is coloured by allowing the juice to stay in contact with the skins. It also absorbs tannin from the stalks and pips, which gives the wine longer life. The longer the juice or ‘must’ remains in contact with the skins, the darker the wine will be.
For white wine, there is no need for skin contact, so the grapes are usually de-stalked on arrival at the winery and a special press used to extract the juice.
Big, powerful whites are allowed some skin contact; not to gain colour, but to acquire body.