First, a lesson in wine geography and nomenclature.

Readers familiar with the official A.O.C. system — Appellation d’Origine Contrôlée — that governs grape-growing and winemaking in France probably know that there are basic wines from Bordeaux that can be labeled as such and basic wines from Burgundy that can be labeled as Bourgogne. The same is not true, however, for the Loire Valley region. Burgundy is minuscule in extent compared to Bordeaux, while Bordeaux is dwarfed by the Loire Valley, noted for being France’s largest and most diverse vineyard and wine-producing area. Grape varieties in Burgundy and Bordeaux, to stay with these handy examples, are limited and consistent; the Loire Valley is blessed — some would say cursed — with a dizzying array of grape varieties. If you picked up a bottle labeled Bourgogne Blanc, you could count on chardonnay being inside the bottle (well, yes, there’s a little pinot blanc in those vineyards); similarly, you would know that Bordeaux Blanc would be a blend of sauvignon blanc and semillon, perhaps with a touch of sauvignon gris or muscadelle. What would be inside a bottle labeled generically as Loire Valley Blanc, however, would be anybody’s guess.

This little disquisition leads to the Wine of the Week, the Pascal Jolivet Attitude Sauvignon Blanc 2009, which carries the designation Vin de Pays du Val de Loire. “Ah ha,” you crow, “there it is, F.K. ‘Val de Loire.’ Loire Valley.” Ah ha, yourself. Notice that this wine is a Vin de Pays, a “country wine,” and therefore a step below the A.O.C. wines in the French scheme of vinous things. Once known by the rather meaningless title Vin de Pays du Jardin de la France, the name was changed to Vin de Pays du Val de Loire in 2007, lending a regional identity which is still somewhat misleading, since this Vin de Pays encompasses 14 departments..

Now, here’s the interesting part. The grapes for this wine derive from two vineyards in the Touraine A.O.C., a Central Loire area rich in history and grand chateaux and a long heritage of winemaking. A Touraine Blanc A.O.C. does exist; the wine can be a blend of chenin blanc, sauvignon blanc, arbois and up to 20 percent chardonnay. There’s even an appellation for Sauvignon de Touraine. So, why did Pascal Jolivet elect to label this wine as VDP du Val de Loire rather than the A.O.C. Sauvignon de Touraine? The clue perhaps lies in the letters “I.G.P” after the VDP designation on the label. The initials stand for Indication Géographique Protégée — “protected geographical region” — and it’s part of a five-year modernization of wine regulations launched by the French government in May 2008. IGP will replace the VDP level of wines, and among other easing of the former rules, it will allow producers to make wines from whatever grape varieties they chose and to take grapes from two or more regions. (It also allows the use of wood chips instead of oak barrels.)

Anyway and finally, the Pascal Jolivet Attitude Sauvignon Blanc 2009, made all in stainless steel, is a charming wine with enough seriousness about it to demand some consideration. The color is very pale straw-gold. Aromas of lemon and lime are imbued with elements of limestone and flint and hints of grapefruit skin and apple skin. There is indeed a bit of “attitude” about the wine, evidenced in its bright spiciness and the boldness of its clean acidity. Flavors of roasted lemon, quince and ginger are bolstered by deep, pervasive minerality, a sort of chalk over limestone foundation, while the texture is both lively and supple. The finish is rounded with a bracing bell-tone of grapefruit pith. Alcohol content is an eminently sane 12.5 percent. This was terrific with seared sock-eye salmon, potato salad and chard. Very Good+. About $17.

Imported by Frederick Wildman and Sons, New York. A sample for review.