Wine · Terminology
Acidity
The tart, mouth-watering component that gives wine its freshness and its structure.
Acidity is the tart, mouth-watering element of a wine — the thing that makes you salivate a beat after you swallow. It comes mostly from the grape itself: tartaric and malic acid are present in the berry, and lactic acid appears later if the wine goes through malolactic conversion.
Acidity is a structural component, not a flavour. It is what keeps a sweet wine from tasting cloying, what makes a light white refreshing, and what lets a wine age for decades. Wines are described on a scale from low through medium to high, judged by how much your mouth waters, not by how sour the wine smells.
In practice
- Grapes lose acid as they ripen, so picking date is the grower's main acidity lever.
- Cool climates hold acidity; warm climates burn it off — the single most useful rule in blind tasting.
- Naturally high-acid varieties: Riesling, Chenin Blanc, Nebbiolo, Sangiovese.
- In warm regions, winemakers may acidify the must with added tartaric acid; in cool ones they may soften it with malolactic conversion.
Where you'll meet it
- Every structured tasting note: acidity sits alongside tannin, alcohol, body and residual sugar.
- German Prädikatswein, where high acid balances high sugar.
- Champagne, where searing base-wine acidity is the whole point.
How to judge it
Acidity is measured on the sides of the tongue and in how quickly saliva returns. A reliable test: swallow, then count. If your mouth floods within a second or two, you are looking at high acidity.
Two traps:
- Sugar masks acid. A sweet Riesling can carry more measurable acid than a bone-dry Chardonnay and still taste softer. Judge the salivation, not the sweetness.
- Alcohol masks acid too. A hot, 15% red can read "soft" when its acid is merely outgunned.
Why it matters
- Ageing. Acidity is a preservative. Wines built to last — Riesling, Chablis, Barolo, vintage Champagne — are almost always high-acid.
- Food. Acidity is what makes wine work at the table: it cuts fat and refreshes the palate between bites.
- Diagnosis. Too little and the wine is flabby; the wrong kind — acetic — and it is showing volatile acidity.
Related terms
- Tannin — the other structural pillar
- Flabby — what a wine tastes like without enough acid
- Volatile acidity — the fault, not the structure
- Malolactic conversion — softening malic into lactic acid