Citric acid is naturally found in citrus fruits, including oranges, limes and lemons. It is usually produced in powdered form and it easily mixes into liquid. Citric acid has many household uses, and there are many products in which it is an ingredient.
Citric acid is used by photographers who do not like the smell of an acetic-acid stop bath. Photos are placed in stop bath to halt the chemical action of the developing agent.
Citric acids like lemon juice can be used as cleaning products. Citric acid can help dissolve hard water stains on shower doors. It can also remove tarnish from brass and copper and clean mild rust stains and soap film. Use caution when cleaning wood furniture with citric acid--it can bleach the surface.
Citric acid is a natural antioxidant. Antioxidants assist in skin repair and help strengthen blood vessels. Citric acid is used in lotion and facial creams. Citric acid helps strip minerals from water, so it is used in small quantities to produce shampoo. Too much citric acid can strip your hair of vital minerals and even bleach it, however. Excessive exposure to citric acid can also cause mild skin irritation.
Citric acid is used along with sodium bicarbonate (baking soda) to create "bath bombs." The combination produces carbon dioxide, which gives your bath an effervescent feel. The antioxidant properties in citric acid are one of the reasons many people purchase bath bombs.
Citric acid has a unique and tangy flavor. It is used to make vitamin C tablets and other medicines taste like citrus fruits. Citric acid is also used to flavor soft drinks such as Sprite, and it is used to make candy sour. Chefs use citric acid as a meat tenderizer.
Citric acid can bond to minerals and metals in a process called chelation. Certain minerals such as calcium can be combined with citric acid to aid in the digestion of the minerals. Calcium citrate is more easily absorbed by the body than calcium alone once it goes through the chelation process. Stomach acid tends to decrease as people age, which makes it harder for the body to break down vitamins and minerals. This is why chelated vitamins are typically recommended for older people.