The Western Loire. Three regions, three grapes to remember.

A diverse, mostly white region

The Loire is France's third-largest producer of AOC wines. Most of its production is white, and the major white grapes are Chenin Blanc, Sauvignon Blanc and Melon de Bourgogne. Sauvignon Blanc belongs mainly to the eastern Loire, so this episode concentrates on the others, plus the red grape Cabernet Franc.

Host Christy Canterbury MW finds Loire reds underrated, and explains why. A wine does not need to be powerful to age well; it needs concentration, complexity and good structure. Old Chinon, she says, offered mind-bending complexity without breaking the bank. A handy memory aid from the episode: Touraine means Cabernet Franc, Anjou-Saumur means Chenin Blanc, and the Nantais means Melon de Bourgogne.

Cabernet Franc in Touraine and Saumur

France is the world's largest producer of Cabernet Franc, known locally as Breton. While it plays a supporting role in Bordeaux blends, the Loire is where it shines on its own, above all in Chinon and Bourgueil in Touraine and Saumur-Champigny in Anjou-Saumur. Cabernet Franc is a parent of both Cabernet Sauvignon and Merlot.

Expect raspberry, bramble and bell pepper aromas, with darker blackcurrant fruit in warmer vintages. The best wines have the tannic structure to age for many years. Chinon in particular has a natural aromatic generosity, and traditional producers age their wines in older, larger barrels, so the fruit and site speak more loudly than toasty new oak. For students, this is a classic example of a cool-climate red with high acidity and herbaceous notes.

Chenin Blanc: dry, sweet and sparkling

Chenin Blanc is one of the most versatile white grapes in the world, made into sparkling, still dry and sweet wines. It has naturally high acidity and a distinctive aroma often described as wet wool.

Near Angers, Savennières makes full-bodied, intensely mineral dry Chenin from slate and volcanic soils, with great longevity. In Touraine, Vouvray ranges from dry to sweet and from still to sparkling. Look for the terms Sec, Sec-Tendre, Demi-Sec and Moelleux, but they are not always on the label. Pickers may pass through the vineyard several times, in selective tries, to gather grapes at different ripeness levels.

Along the Layon river, Coteaux du Layon is never dry, and the grapes are often affected by noble rot. Within it are Chaume Premier Cru, Quarts de Chaume Grand Cru and Bonnezeaux, among the world's great sweet wines, with honey, acacia and ripe yellow fruit always balanced by fresh acidity.

Muscadet and the sur lie experiment

Near Nantes, where the Loire meets the Atlantic, Melon de Bourgogne makes Muscadet. The grape came from Burgundy in the Middle Ages and is not very aromatic on its own, so many producers age the wine sur lie, on its lees, for weeks or months. Muscadet cannot exceed 12.5% alcohol by law, which keeps it light, salty and bitingly dry.

The experiment explains the term you will find on so many Muscadet labels. Using baking yeast and hand-pressed grapes, the hosts show the difference between gross lees and fine lees, why winemakers rack wine off the gross lees, and what bâtonnage, or lees stirring, does to texture and flavor. A time-lapse film shows fine lees settling in a real bottle.

Food pairings and blind tastings

Andreas Larsson, World's Best Sommelier 2007, pairs a Muscadet Sèvre-et-Maine Sur Lie from Château de la Ragotière with moules marinière, a natural match of sea and seaside vineyard. Later he cooks a quick crab pasta with lime zest and pink peppercorns for a richer white.

Both hosts face a blind tasting. One of them even tastes wearing a blindfold. Listen to how they describe development, tannin and texture, and find out which appellations they name before the bottles are revealed.