100% Riesling

Food pairings: Oysters and other shellfish, sushi, white fish, or on its own as an aperitif.

Winemaking: Whole bunches are pressed slowly over about nine hours, and the juice ferments with indigenous yeasts in stainless steel. The wine then rests on its lees for a year and is bottled dry.

Vineyards and terroir: Clos Mathis is a stone-walled clos in Ribeauvillé, in line with the grands crus Geisberg and Kirchberg. The vines grow on terraces cut into a very steep south-east-facing slope of granite and gneiss with poor fertility. Hot days are tempered by cool winds that come down the valley at night, so the Riesling ripens slowly and keeps its acidity and finesse. The vineyard is certified organic and biodynamic.

Family and history: The clos belongs to Hubert Mathis, Domaine Ostertag's long-serving former vineyard manager, who inherited it from his parents and rebuilt it entirely. He sold the grapes to a local merchant until 1997, when he and André Ostertag decided to bottle this historic site, esteemed since the Middle Ages; it has been released as Clos Mathis since the 2000 vintage. Domaine Ostertag is based in Epfig and is now led by André's son, Arthur Ostertag.

In the pictures: Arthur Ostertag pruning the vines; and André Ostertag with Hubert Mathis. Photographs via Mes Vendanges.