Creating the Flavor

We now know that growing grapes are covered with a natural bloom, a waxy film which traps the cells of wind- and insect-borne molds and wild yeasts. A grape-skin may have as many as 10 million yeast cells on it. Only a mere a hundreth or so of these cells are ones from yeasts that will stimulate fermentation processes leading to wine.

Enzymes in wine yeasts convert a grape's sugars into alcohol and create the numerous by-products which partially account for a wine's flavor. In some old European vineyards, the grapes and yeasts seem to have established a natural harmony which brings out the grapes' best qualities in the wine. Nowadays though, most wineries, even in Europe, improve on Nature by adding pure cultures to desirable yeasts and by using chemicals to suppress any undesirable ones.