Noix de Grenoble and Walnut Culture
The Noix de Grenoble (AOC 1938, the first AOC granted to a fruit in France) is the walnut of the Dauphiné — grown in the valleys of the Isère, Drôme, and Savoie around Grenoble, and the foundation of a walnut culture that pervades every aspect of the region's cuisine from oil to liqueur to pastry. Three varieties are authorized under the AOC: Franquette (the dominant variety — large, easy to crack, rich and buttery), Mayette (slightly smaller, more delicate flavor, excellent for confiserie), and Parisienne (vigorous, productive, slightly more tannic). The walnut harvest occurs in September-October: the nuts fall naturally from the trees (or are shaken down) and must be collected within 48 hours to prevent mould. They are then washed, dried to 12% moisture, and graded. Fresh walnuts (noix fraîches, available only September-October) are a seasonal delicacy — the kernel is white, milky, with a texture like fresh cheese and a sweet, green, almost grassy flavor utterly different from the dried walnuts available year-round. In the kitchen: Huile de noix (walnut oil) is the Dauphiné's primary salad oil — pressed from dried walnut kernels, the oil is fragrant, nutty, and perishable (use within 3 months of opening, store refrigerated). Walnut oil vinaigrette is the standard dressing for green salads, for lentil salads, and for the Dauphinois salade de noix (curly endive, walnuts, Bleu de Sassenage, walnut oil vinaigrette). Gâteau aux noix (walnut cake) is the region's signature pastry. Vin de noix (walnut wine/liqueur) is made by macerating green walnuts (picked at the Saint-Jean, June 24, when the shells haven't yet hardened) in red wine with sugar and eau-de-vie for 40 days. Noix confites (candied walnuts in caramel or honey) are the confiserie tradition.