Capsaicin is mainly found in hot pepper plants from the capsicum frutescens family. While most varieties are found in South America, where chilis originated, there are also capsicum varieties in Africa, India and even China. Like bell peppers, which also belong to the capsicum falmiy, not all chili peppers are hot. For example, paprika is from the capsicum family, but it's mild at best. On the other hand, paprika's cousin, cayenne, is scorching hot. It all depends on the heat factor within a particular plant.
Hot peppers even have their own measuring scale for heat, known as "Scoville Units." Mostly used in the food industry, the Scoville heat scale is regarded as the most accurate way to measure the true hotness of a pepper plant. Developed in 1912 by botanist Wilbur Scoville, a pepper's Scoville Unit number is based on how much the ground chili needs to be diluted before no heat is detected. Scoville Units measure the perception of heat in multiples of 100, with bell peppers setting the heat-free baseline at zero Scoville Units, pure capsaicin measuring more than 16 million Scoville Units, and most popular types ranking around 30,000 Scoville units. Until recently, habañero peppers held the world record, with some varieties scoring a searing 300,000 Scoville units. However, in 2000, Indian research scientists tested a chili pepper called Naga Jolokia, from the remote northeastern province of Assam. This devilishly hot Indian chili now holds the dubious distinction of being the world's hottest pepper, with a reported score of 855,000 Scoville units.
About 80 percent of a chili's capsaicin is found in the ribs and seeds, which can be removed to reduce its heat. Capsaicin is also distributed unevenly, in much smaller amounts throughout the flesh of a chili pepper.
Aerosolized capsicum, better known as pepper spray (often used to fend off potential attackers) is now being used to fend off sinus infections, allergies and headaches, thanks to a new nasal spray packed with hot pepper extract.
Always exercise a great deal of care when preparing hot peppers to avoid injury. Check at the produce department to select the pepper with the right degree of heat for your palate. Use rubber gloves when chopping and seeding and don't touch your eye during preparation as the oil in the hot peppers will cause a burning sensation—advice spoken with the voice of painful experience!
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