Sémillon

Sémillon's exact origins are murky. Written records place it along the Garonne and Dordogne rivers in southwest France by the 16th and 17th centuries, in what's now Bordeaux and the Dordogne. It became the grape behind Sauternes and Barsac early on, and for a long time was one of the most widely planted white grapes in France.

It crossed to Australia in 1832, brought over among several hundred vine cuttings collected by James Busby. For decades it was grown there under names that had nothing to do with the actual grape, "Hunter River Riesling" and "Shepherd's Riesling," and wasn't consistently labelled by its real name until the 1980s. It also became, at one point, the single most planted grape in South Africa, before Chenin Blanc overtook it.

• Sauternes & Barsac, France - Sémillon's majority-grape role here, combined with the local mist-then-sun mesoclimate, produces the world's most famous botrytised sweet wine.

• Graves & Pessac-Léognan, France - blended with Sauvignon Blanc and sometimes a touch of Muscadelle into serious, age-worthy dry whites; still Bordeaux's third most planted grape overall, behind Sauvignon Blanc and Chardonnay.

• Hunter Valley, Australia - bone-dry and unoaked, picked early to keep alcohol low, with all its honey and toast character developing later in the bottle rather than a barrel.

• Margaret River, Australia - blended with Sauvignon Blanc into a crisp, aromatic pairing that's been a regional calling card since 1979.

Sémillon's thin skin is the whole story here. It's exactly what makes the grape vulnerable to botrytis cinerea, the "noble rot" that shrivels ripe berries and concentrates their sugar, acid, and flavour. That vulnerability is a liability almost everywhere except Sauternes and Barsac, where the local mist-then-sun mesoclimate turns it into an asset.

Left unchecked, Sémillon is a vigorous, naturally high-yielding vine, so quality producers prune hard and keep yields down, generally to somewhere between 25 and 40 hectolitres per hectare. It buds and ripens mid-season, around the same time as Merlot in Bordeaux, and does best on gravel or clay-limestone soils that drain well but hold just enough water through dry spells. On its own, the grape isn't especially aromatic, which is part of why site and winemaking do so much of the work in defining its final character.

Sémillon splits into a handful of genuinely distinct paths depending on where it lands. In Sauternes and Barsac, pickers move through the vineyard in multiple passes, sometimes five or six per vintage, taking only berries with the right degree of botrytis. The must is pressed several times and fermented slowly, often in new oak, until high alcohol stops the yeast naturally and leaves the wine full of residual sugar.

In dry Bordeaux blends like Graves Blanc, Sémillon is usually paired with Sauvignon Blanc for acid and sometimes a touch of Muscadelle for aromatics; the better examples see oak, adding texture and helping the wine age.

In the Hunter Valley, the approach flips almost everything about Sauternes: grapes are picked early, well before full ripeness, to keep alcohol low (often 10–11%) and acid high. Fermentation happens in stainless steel, with no oak and no malolactic fermentation, and the wine is bottled young and bone-dry. The complexity that eventually shows up, honey, toast, beeswax, comes entirely from years in the bottle, not from a barrel.

Sémillon's aroma changes so much by style that four aromas can't describe one wine so much as the grape's whole range, from young and dry to decades-old and sweet.

On the palate, dry young Sémillon is light to medium in body with only moderate acidity, the Hunter Valley the clear exception, where early picking pushes acid noticeably higher than other dry styles. With age, dry examples turn golden and develop honey and dried stone fruit, closer in character to an aged Chardonnay than to what they tasted like on release. In its sweet, botrytis-affected form, Sémillon is luscious in texture from the glycerol botrytis produces, with acidity high enough to keep all that sugar from tasting flat.

• Château d'Yquem (Sauternes, France)
  The benchmark for botrytised Sémillon, and the wine most responsible for the grape's reputation. Multiple picking passes through the vineyard chase exactly the right degree of noble rot, vintage after vintage.

• Château Climens (Barsac, France)
  Barsac's answer to Yquem, built on Sémillon rather than the Sauvignon Blanc-heavier blends common elsewhere in the appellation. Also home to a newer dry white, proof the grape has range beyond sweet wine even at a classic botrytis address.

• Tyrrell's (Hunter Valley, Australia)
  Vat 1 is Hunter Valley Semillon's most decorated wine and its de facto benchmark, picked early and bottled bone-dry with zero oak. Proof that Sémillon's honey and toast can come entirely from bottle age, not a barrel.

What Sémillon pairs with depends almost entirely on which of its several styles is in the glass.

• Oysters and scallops - Young, dry Sémillon's acidity and light body suit delicate seafood, sushi included

• Roast chicken or mild curry - Aged dry examples, with their honeyed, toasty character, can handle more weight on the plate

• Roquefort - The classic match for sweet, botrytised Sémillon; sharp, salty blue cheese against concentrated sweetness

• Foie gras - The other traditional Sauternes pairing, rich enough to stand up to the wine's intensity