Potassium nitrate is a white solid. Another name for this nitrogen source is saltpetre, and it forms naturally in caves. With the development of the Haber process, people achieved the ability to produce potassium nitrate on an industrial scale. This compound has a range of functions that include uses in food science, health and chemical applications.
Background
Each molecule of potassium nitrate contains an atom of potassium, an atom of nitrogen and three atoms of oxygen. At room temperature, the molecule is a solid white or gray mineral. According to Chemistry Daily, potassium nitrate is not hazardous upon normal contact with eyes or skin. Ingestion can cause diarrhea or other gastrointestinal disturbances, and inhalation can be fatal. Bacteria naturally produce potassium nitrate through nitrogen fixation, or oxidizing ammonia from urea.
Food Preservation
Salts help to preserve meat by killing bacteria and preventing spoilage. Nitrate salts such as potassium nitrate change into nitrites during processing and storage. Nitrites contribute the pink color in many cured meats such as hams, sausages, and corned beef. The Food and Drug Administration lists nitrates as generally recognized as safe ingredients. According to the University of Minnesota Extension, a lethal dose of potassium nitrate would be about 30 to 35 g in one dose, or the amount in about 18 lb. of cured meat.
Fertilizer
Plants need potassium to grow. If the soil does not naturally provide enough potassium, plants need an external source. A common source of potassium is from fertilizers. According to Michigan State University, fertilizers with potassium nitrate, or nitrate of potash, provide both potassium and extra nitrogen to crops. This type of fertilizer is expensive, and the most common use for potassium nitrate fertilizers is for high value crops such as tomatoes and leafy green vegetables.
Gunpowder
According to the Chemistry Daily, the Chinese made gunpowder with potassium nitrates for hundreds of years. Historically, the production of nitrates required at least a year. People would mix manure, organic matter, and straw in a compost pile. Throughout the year, they consistently watered the nitrate bed. The pile eventually decomposed and produced nitrates. As an ingredient in gunpowder, nitrates supply oxygen to allow the explosion to occur. Now, potassium nitrate is sometimes a component of fireworks.
Blood Pressure
Hypertension, or high blood pressure, can be a risk factor for heart disease or stroke. Potassium nitrates might act as hypotensives because the body converts dietary nitrates into nitrites. Nitrites are vasodilators, which lower blood pressure. A study in the journal Hypertension from the American Heart Association reported that the blood pressure in healthy people who took potassium nitrate supplements dropped. This drop was similar to the decrease among people who ingested nitrates from the natural dietary source of beet roots. Research about the effects of potassium nitrate on blood pressure continues, and you should consult your doctor if you have concerns about your blood pressure.
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