Merlot blanc

Merlot blanc is a white French wine grape variety that came from a natural crossing of the Bordeaux wine grape Merlot and the Cognac grape Folle blanche. The grape is distinct from Merlot gris which is a pink-skinned color mutation of the red wine grape Merlot and is sometimes used in vin gris and rosé wines. Plantings of Merlot blanc were first discovered in 1891 but cuttings of the vine have not been widely propagated and the variety is very rare. It is not used to make the sweet White Zinfandel-style wine White Merlot that is made by some California wine producers. Those wines are made from a saignee of red Merlot wine.

When Merlot blanc was first discovered, it was thought that the vine was a white-berried color mutation of Merlot in a similar relation to how Grenache blanc is a color mutation of Grenache and Pinot blanc is a mutation of Pinot noir. However, DNA analysis conducted by the University of California-Davis and noted ampelographers such as Carole Meredith confirmed that Merlot blanc was distinct from Merlot (itself the result of a crossing of the Bordeaux grape Cabernet Franc and the Brittany/Charente grape Magdeleine Noire des Charentes) but rather was an offspring of Merlot. Inheritance analysis of 55 genetic markers spread out over 9 chromosomes, showed that Merlot blanc was the result of a crossing of Merlot with the Cognac/Armagnac grape Folle blanche.

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