Ingredients: Citric acid. 

Product Information: Citric acid is completely natural, produced by cells during the Krebs cycle. The acid gets its name from the citrus fruit family, which includes lemons, limes, oranges, tangerines, and grapefruits. Citrus fruits, especially the more sour ones like lemons and limes, owe their sharp taste to citric acid. Because of its characteristic tart flavor, citric acid is often added to soft drinks, cheeses, ice creams, alcoholic beverages, breads, and candies.