Acidity in coffee is a sensory perception, not simply a chemical measurement. Multiple organic acids contribute differently to how acidity is experienced on the palate. Citric acid creates bright, citrus-like sensations, while malic acid produces apple-like sharpness. Phosphoric acid contributes sparkling acidity without sourness.
The balance between acids and sugars determines quality perception. High acidity without sufficient sweetness is often perceived as sour, while balanced acidity enhances complexity. Roasting alters acid composition by breaking down unstable acids while concentrating others.
Brewing further modifies acidity perception. Higher extraction yields emphasize bitterness, while under-extraction highlights sharp acids. Water mineral content also affects how acids are perceived, as calcium and magnesium bind differently to organic acids.
Understanding acidity as a sensory interaction rather than a defect allows professionals to design roast and brew profiles that highlight brightness without harshness.