Noix de Grenoble

Appearance & taste

Noix de Grenoble are in-shell walnuts of one or more of the varieties Franquette, Parisienne and Mayette. They are sold fresh or as dried nuts and in both cases have a diameter of at least 28 mm. The shell is clean and sound, the kernel firm and fleshy, pale to light brown. With fresh nuts the shell comes off easily, and the kernel has a natural moisture content of at least 20 %; for dried nuts it is at most 12 %.

On tasting, both fresh and dried nuts show a bitter note and aromas of fresh bread and hazelnuts.

Production

The trees stand in orchards of limited density, each with at least 100 m² of space. Young trees receive formative pruning; after that they are cut back every two to three years so that light reaches the inside of the crown. Harvesting takes place at the end of September on a date set jointly each year according to ripeness in the various sites, when the partitions inside the nut have turned completely brown.

The nuts are quickly sorted, washed and dried no later than 36 hours after harvest, usually with moderately warm air of up to 30 °C passed through the layer of nuts, and by smaller producers also in the open air on slatted racks. They are then sorted by size. All steps from harvest to packing take place in the area. Sorting and packing are done in one step at the same place, in containers of at most 10 kg for fresh and 25 kg for dried nuts, so that the shells do not break. Fresh nuts leave the area no later than two months after the start of the harvest, dried nuts by 31 December following the harvest. Each pack bears a bright red, numbered seal of authenticity; this system has existed since 1968.

Origin & history

The area comprises 261 municipalities in the farming landscapes of Le Grésivaudan, Chambarans and Bièvre along the Isère valley: 184 in the department of Isère, 48 in Drôme and 29 in Savoie. At around 300 m altitude the mean annual temperature is 10.5 °C, with 800 to 1,100 mm of rain a year. The winters are cold, with 65 to 100 days of frost, and at the same time the driest season; from August the temperature falls by 10 °C in two months, so that the nuts ripen slowly and evenly. Autumn is the wettest season. According to the specification, in the humid air and through the thick shell the kernel releases water slowly and evenly, which contributes to the fine aroma and prevents the fats from going rancid.

The archives of Grenoble mention dues paid in walnuts at the end of the 11th century, and the account books of the lords of the castles in the 14th and 15th centuries also record production. By the end of the 18th century grafting of the trees was widespread, and with better transport links the English and American markets were added; even before 1900, producers in the village of La Rivière pooled their exports to the USA. The producers’ association was founded in 1927, and in 1938 the designation of origin was introduced by decree of 17 June, based on the three local varieties. According to the specification, tree nurseries in Vinay, Vif, Saint-Marcellin and, from about 1960, in Chatte partly explain the uniform stock of trees. Walnut groves and traditional drying sheds shape the landscape.