Grape

A 8,000-year-old fermentation

Wild grapes were fermented by humans long before they were systematically cultivated. Archaeological evidence from Georgia (the country) shows wine production dating to at least 6,000 BCE. The Caucasus region — modern Georgia, Armenia, and northern Turkey — is the best candidate for the original domestication site of Vitis vinifera.

Wine’s biology

Grape skins carry yeast naturally on their surface. Crushed grapes ferment spontaneously: yeasts consume the sugars and produce ethanol and CO₂. Modern winemakers usually inoculate with cultivated yeast strains for control, but “natural wines” still rely on the wild yeasts on the skins. Different yeast strains, terroirs, and fermentation conditions produce dramatically different wines from the same grape.

Old World vs. New World grapes

• Vitis vinifera (Old World) — origin in Eurasia. Dominant in commercial wine and table production. Susceptible to phylloxera (a root louse).
• Vitis labrusca (American) — Concord, Niagara, Catawba. Phylloxera-resistant. Used for juice, jelly, and some sweet wines.

The phylloxera epidemic of the 1860s nearly destroyed European wine production. The fix was grafting V. vinifera scions onto American rootstock — a horticultural rescue still standard in most of the world’s vineyards today.

Resveratrol and the French paradox

Red grape skins contain resveratrol, a polyphenol that received intense study in the 1990s for possibly explaining the “French paradox” — the observation that French populations consume relatively saturated fats yet have low cardiovascular disease rates. Subsequent research has been mixed; the dose of resveratrol from a glass of wine is far below the doses showing effects in laboratory studies. It’s likely not a single compound but a constellation of dietary and lifestyle factors.