Grape vines have a wonderful tendency to mutate. Wine growers are taking advantage of these mutations to use familiar varieties to make new flavors in new areas.
Unfortunate souls deprived of wine by virtue of Prohibition, imprisonment, or military service have made tasty wines from raisins, table sugar, and tea. In fact, with the addition of the proper nutrients for the yeast (which can be purchased at any winemakers’ supply), there's a whole world of fermentable possibilities out there. We could make wine from flat coca-cola, pancake syrup, Hawaiian punch, or crushed and macerated breakfast cereal. In fact, fermentation is so close to inevitable that most of these products contain chemicals called ‘preservatives’ whose sole purpose is to make them inhospitable to yeasts and therefore unfermentable.
We could make all these different wines, but we don't. With a few exceptions, such as cider made from aples, perry from pears and mead from honey, we make wine from grapes and grapes alone. ( By the way, compound wines, made from grapes and other fruit and flavors used to be more common. It wasn’t until 1907 that France enacted a law defining wine as a drink made from grapes and grape juice only.)
Grape varieties
In fact, we restrict our winemaking to a handful of varieties of grapes. Why? First of all, grapes are marvelously convenient for the purpose. When they're ripe, grapes reach a concentration of sugar that is high enough to supply the yeast with food enough to make 10 to 15 percent alcohol from their juice. The native acid in grapes, tartaric acid, is a good weapon against bacterial spoilage so grape wine will last longer than wines made from other fruit.
Grape juice also makes a naturally clear wine with no pectin from the fruit's skin to cloud it. Grapes can be grown in almost any temperate location and can be cultivated to give staggering amounts of fruit per acre. Grape vines have another advantage. They have an incredible tendency to variability. (Wheat, that other pillar of Mediterranean civilization, has the same tendency.)
Wine Cloning
If cuttings of a vine are taken and transplanted in several locations, each having different growing conditions, each young vine will adapt itself and its habits to the new environment. This “cloning” of vines accounts for a great deal of the spread of wine varieties from one place to another, and the change in form and habit explains why there is so much confusion over whether one named variety is related to another. (The mapping of DNA will, no doubt, undo a lot of the confusion about the ancestry of various grape varieties. Recently it was established that the mysterious and elegant Zinfandel is genetically identical to Primitivo from Apulia in Italy and that both of them are descended from a common Croatian ancestor.)
This kind of variability doesn’t involve genetic change: it’s simply a matter of a different expression in each environment of the vine’s genetic potential. But grapes also have a remarkable tendency to develop spontaneous genetic mutations, or bud sports. A vine that usually produces small berries may all of a sudden produce a bud whose berries are huge.
The black-fruited Gamay vine sometimes produces branches with white grapes. Seedless table grapes are also the result of such a bud sport. This is true genetic change, and the resultant growth can itself be cloned, producing a new variety. As wine making becomes more international, witnegrowers are looking to the ability to clone these random mutations has enabled them to grow established grape varieties in new areas. New strains of Pinot Noir, for instance have been cloned from bud sports of the Burgundian originals and planted in places, like California where Pinot never did well. A clone of Pinot Grigio (itself a clone of Pinot Noir) called Rulander shows more fruitiness than its parent.
It takes a long time before a cloned vine gives fruit and longer still for the wine to be fairly evaluated, so progress is slow. The expense involved means that innovators are going to be conservative and cautious (no wasabi-scented pinot grigio for instance). But thanks to cloning, we can look forward to better wine from newer wine regions.
