Acidity in wine refers to the fresh, tart, and sour attributes that help to balance the sweetness and bitterness of wines. It’s what makes your mouth water and is crucial for the structure and longevity of a wine. Acidity is naturally present in the grapes, and its level can vary depending on the climate where the grapes are grown—cooler climates often produce grapes with higher acidity. Wines with high acidity can feel crisp and refreshing, while those with low acidity might taste richer and rounder.