Nosiola

Local lore traces Nosiola back to Raetica, a white grape that Roman authors associated with the Alpine foothills of northern Italy. Nobody knows what Raetica actually was, so the story cannot be checked. Genetics offers firmer ground. A 2007 microsatellite study revealed a parent-offspring link between Rèze, an ancient variety of Switzerland's Alpine Valais region, and two white grapes of Trentino: Groppello di Revò and Nosiola. In each pairing Rèze is the more probable parent, since it is documented far earlier (it turns up in records from 1313), whereas the two Italian varieties are first mentioned only in the nineteenth century. Nosiola's other parent has never been identified.

That kinship accounts for one of its old synonyms, Groppello Bianco, which echoes the connection to Groppello di Revò. Spargelen was a further local name, used in Alto Adige, where the vine was also once grown; both sides of the regional boundary could therefore call it native, though it is now cultivated only in Trentino. The name most likely derives from nocciola, Italian for hazelnut, alluding to the nutty character of the wine; another proposal ties it to the colour of ripe berries. A weaker etymology derives it from a dialect word for a small eye. Nosiola is also sometimes mistaken for Durella, a variety from the Veneto.

Nosiola ripens in the middle to late part of the season. Early budding exposes it to spring frost, and the vine is susceptible to powdery mildew, as well as to sour rot when vintages turn humid. Bunch stem desiccation is a persistent problem; it can halt sugar accumulation before the berries have fully ripened. Thick skins help the grapes endure the extended drying required for Vino Santo. The vineyards used for that wine lie on the slopes of the Valle dei Laghi, in the area between Trento and Lake Garda, where the Ora breeze off the lake shapes the climate. Old vines are favoured for the dessert wine, while growers making dry wines have preferred hillside sites such as those near Pressano, close to Lavis.

Vino Santo Trentino is the traditional expression. Grapes are picked in autumn and dried on racks in lofts through winter; botrytis often develops, and berries can lose 60 to 80 per cent of their weight. They are pressed around Holy Week, the source of the wine's name, and the very concentrated must ferments slowly in small oak barrels over several years. Bottlings are typically released after seven to ten years, and good examples show apricot, quince, orange peel, honey and candied citrus on a frame of marked acidity. Annual output is only a few tens of thousands of half-bottles.

Dry Nosiola, bottled as Trentino DOC Nosiola, is fragrant and zesty, with citrus, peach and almond or hazelnut notes, and some bottlings carry richer, sweeter-toned fruit. Nosiola also contributes to the blended Sorni Bianco, alongside varieties such as Müller-Thurgau, Sylvaner and Pinot Bianco, and may appear in the Valdadige/Etschtaler DOC.