Baking soda, otherwise known as bicarbonate of soda, sodium bicarbonate, and, less commonly, saleratus, is a chemical salt with diverse practical uses. With a chemical formula of NaHCO3, it is a white powder with crystalline grains. Although it can be produced by artificial means, in its natural form, baking soda is called nahcolite, taking its name from its chemical formula.
Sodium bicarbonate is weakly alkaline. As such, it acts to neutralize acids and break down proteins. This quality accounts for its usefulness as a tenderizer and a leaven. Also, its neutralizing action on acidic scent molecules makes it an effective deodorizer. Added to the water when doing laundry, baking soda stabilizes the pH level, enhancing the detergent’s effectiveness. It may also be added to swimming pool water to balance the pH and keep the water clear.
The most common practical use for baking soda is as a leavening agent in baking. In combination with a liquid and an acid, it undergoes a chemical reaction that releases bubbles of carbon dioxide. Trapped in batter or dough, these carbon dioxide bubbles enable the baked good to rise. Baked goods leavened with baking soda, therefore, generally have a light crumb and are aerated with many holes left by the escaping bubbles of carbon dioxide.
This chemical should not be confused with baking powder, which has added acidifying and drying agents (typically cream of tartar and starch, respectively). It is pure bicarbonate of soda.
Baking soda also has other uses in cooking. A pinch added to tomato sauce while cooking, or coffee while brewing, will reduce its acidity. A small amount added to the soaking water of beans will hasten the softening and cooking processes and reduce the beans’ propensity to cause flatulence in the eater. It's an effective meat tenderizer, and it can be added to stews or rubbed directly on a cut of meat, and then rinsed off before cooking, to make the meat more tender.
When heated, baking soda undergoes a chemical reaction that gives off carbon dioxide, which makes it useful in extinguishing small grease or electrical fires.
Baking soda’s finely gritty texture makes it an excellent, gently abrasive cleaner. It is inexpensive, environmentally friendly, fragrance-free, and safe for nearly all surfaces, making it ideal for household use. As a mild abrasive agent, it can also be used in place of toothpaste. Sprinkled around the exterior entrances to and foundations of homes, it may stop ants and other insects from crawling in, as it is irritating to their chitinous exoskeletons and they usually avoid it.
As an acid neutralizer, baking soda has long been favored for its various first-aid applications. Dissolved into a lukewarm bath, it will soothe the discomfort of sunburn and the itch of poison ivy. Made into a paste with cool water and applied directly to the skin, it will ease the pain of bee stings. One-half teaspoon (2.3 g) mixed into 4 ounces (120 ml) of water can be taken as an antacid. Those taking prescription medications or following a reduced-sodium diet should check with a medical professional before consuming sodium bicarbonate.