The pH of citric acid is 2.2. pH measures the acidity and alkalinity of a substance or solution. The lower the number, the higher the acidity. The greater the number, the higher the alkalinity. On the scale, 7 is neutral.
Citric acid is a weak, organic acid commonly utilized as preservative. Citric acid commonly is used not only as a food and beverage preservative but also to add a sour taste to a product. At room temperature, citric acid appears in the form of a crystalline, white powder. Lemons, limes, oranges and grapefruit represent examples of fruit that contain citric acid.