Two bottles of Chardonnay are open on the pass. One is a lean, steely Chablis; the other a broad, buttery Californian. A guest tastes both, looks up, and says: "These are the same grape? Are you sure?" You are sure - and now you need to explain why they are so different.
From grape to glass, in outline
Every wine follows the same four steps. What changes is what the winemaker does at each one.
- Harvest - grapes are picked. Riper grapes mean more sugar, so more alcohol, and softer acidity.
- Crush and press - whites are usually pressed straight away, so the juice never sits with the skins. Reds are fermented on the skins to extract colour and tannin.
- Ferment - yeast turns sugar into alcohol. Ferment until the sugar is gone and the wine is dry. Stop the ferment early, or sweeten afterwards, and the wine keeps some sugar.
- Mature and bottle - in inert stainless steel (keeps the wine fresh and fruity) or in oak (adds flavour and texture).
Rose is made by giving black grapes a short time on the skins. Sparkling wine gets a second fermentation that traps carbon dioxide. Fortified wine has grape spirit added - before the ferment finishes if you want it sweet, after if you want it dry.
Climate does most of the work
Grapes ripen faster where it is warm. That single fact drives style.
| Cool climate | Warm climate | |
|---|---|---|
| Acidity | High | Lower |
| Alcohol / body | Lower, lighter | Higher, fuller |
| Fruit character | Green, citrus, tart red fruit | Ripe, tropical, black, jammy |
| White example | Chablis (Chardonnay) | Napa (Chardonnay) |
| Red example | Burgundy (Pinot Noir) | Barossa (Shiraz) |
So the same variety gives a lean, citrus, high-acid wine in a cool place and a ripe, tropical, full-bodied wine in a warm one. This is the single most useful idea in the course: name the grape, then name the climate, and you can predict the style.
Oak
Oak barrels are a flavouring and a texture, not a requirement.
- New oak gives the most flavour: vanilla, toast, smoke, clove, coconut, sometimes a creamy texture.
- Old oak gives little flavour; it mainly softens the wine gently over time.
- No oak (stainless steel, concrete) keeps the wine fresh, primary and fruity.
When a guest says a Chardonnay is "oaky" or "buttery," they are describing the winemaking, not the grape.
Onboard Notes
- The style triangle: grape + climate + winemaking. Change any one and the wine changes.
- "Unoaked" is a selling point for many guests. Keep at least one unoaked white and one oaked white aboard so you can offer both.
- Never say a wine is "better" because it is oaked or riper. Say what it is, and let the guest choose.