Grape-picking  

Grape-picking in the Sauternes and Barsac region starts only when, under the effect of Botrytis Cinerea, the grapes have the required sugar content. Botrytis Cinerea is a rather unpredictable ally that works at its own pace and may improve the grapes on the same bunch at different times. That is why the Sauternes wine-growers pick their grapes entirely by hand as they have to check each bunch to be sure to pick only those that are ready.