Citric acid is a natural compound that can be found in a variety of fruits and vegetables, including citrus fruits (such as lemons, limes, and oranges), as well as strawberries, raspberries, and pineapple. It is also present in some fungi and yeasts. Commercially, citric acid is produced by fermenting molasses or sugars with certain types of bacteria or fungi, such as Aspergillus niger. It is used as an acidulant in food and beverages, as well as in a variety of other industrial applications, including cosmetics, pharmaceuticals, and cleaning products.