What acid is in citrus fruits?

The predominant acid in citrus fruits is citric acid. It is a weak organic acid that occurs naturally in citrus fruits like oranges, lemons, limes, and grapefruits. Citric acid is responsible for the tart and sour flavor of these fruits. It also acts as a natural preservative, helping to prevent spoilage and maintain the fruit's freshness. Aside from its presence in citrus fruits, citric acid is found in various berries and other fruits, including currants, gooseberries, and raspberries.