For which type of wine style is hand-harvesting specifically required in Bordeaux?

Hand-harvesting is specifically required for sweet wine production in Bordeaux due to the delicate nature of the grapes and the careful selection process involved. In regions like Sauternes, the production of sweet wines often relies on the presence of Botrytis cinerea, or noble rot, which enhances the concentration of sugars and flavors in the grapes. This process requires meticulous handling, as grapes need to be picked at optimal ripeness and with individual attention to avoid damaging them.

The labor-intensive approach of hand-harvesting allows for selective picking, where only the affected, perfectly ripened grapes are chosen while the other grapes on the vine can be left untouched. This ensures the highest quality of the final wine, as the producers can select grapes that have been impacted positively by the botrytis.

In contrast, while hand-harvesting is used in other styles like red and dry white wine production for quality reasons, it is not strictly required. For sparkling wine production, mechanical harvesting may be permitted, particularly for large volume production where speed and efficiency are necessary. Thus, the unique requirements of sweet wine production necessitate hand-harvesting in Bordeaux for achieving the desired quality and style.