Chili peppers are used everywhere, from tacos to pad thai, and are growing in popularity. In fact, the average American consumes about 5.9 pounds of chili peppers a year, according to Brendan Borell in his article What’s So Hot About Chili Peppers? (Smithsonian Magazine). These varicolored fruits belong to the genus Capsicum and are a member of the nightshade family, which also includes tomatoes, potatoes and eggplants (aubergines).
Chili peppers were first grown over 6000 years ago in the Americas, and were brought to the rest of the world in the 1400s by European explorers. Since then, chilies have become an integral part of various international cuisines. But why are chili peppers spicy in the first place? What gives the chili pepper its heat?
Capsicums Full of Capsaicin
The compound responsible for the chili pepper’s heat is the chemical capsaicin, part of a food chemical group called vanilloids, and the prime ingredient that gives pepper spray its sting. When ingested, capsaicin triggers pain receptors in the mouth and on the tongue that indicate heat, sending a message to the brain that something hot has been ingested. The human body reacts to the message just as it would to something burning hot – adrenaline starts pumping, the heart speeds up, and the body perspires.
Capsaicin is concentrated in the white flesh on the inside of a chili pepper, as well as coating the seeds.
Why Chili Peppers Develop Their Spiciness
Studies suggest that chili peppers produce higher levels of capsaicin and related substances, or capsaicinoids, as a response to attacks by fungal infection. Scientists found that within the same species of chili pepper, some fruits were hotter than a jalapeno, while fruits from other plants were scarcely spicier than a bell pepper, according to the article Bugs Put the Heat in Chili Peppers on ScienceDaily.com (Aug 8, 2008). The study showed that chilies got hotter in areas where insect and fungal attacks were common, with higher levels of capsaicin, which slows microbial growth.
The anti-microbial properties of chilies may also be one reason they were adapted into the diets of people living in hot, moist climates thousands of years ago, as they reduced the chance of illness from ingesting contaminated food.
How to Measure Heat in Chilies
The amount of heat, or spiciness, in a chili is measured by Scoville Heat Units (SHU). Wilbur Scoville was a Detroit chemist who, in 1912, diluted chili extracts in water “until the heat was no longer detectable by a panel of trained tasters”, according to the Borell article. The number of times the chili was diluted before the heat was undetectable related to the number of Scoville Heat Units it was assigned. A sweet bell pepper has an SHU of zero, while a jalapeno pepper “falls between 2500 and 8000 Scoville Heat Units” (Borell). Pure capsaicin measures 16 million SHUs!
Chilies May Help Fight Cancer
A study by Nottingham University in 2007 showed that capsaicin, the spicy chemical in chili peppers, was able to attack the mitochondria inside cancer cells, triggering cell death, said an article by BBC News: "How Spicy Foods Can Kill Cancers" (Jan 9,2007). The capsaicin did not harm healthy cells nearby. These findings could be significant in future cancer drug research. However, this does not mean that eating huge quantities of chilies will prevent cancer, and the health-conscious should continue to maintain a balanced diet.
In addition to their health benefits, chilies are a delicious addition to all kinds of dishes. From the sweet and mild bell pepper to the fiery jalepeno, the many varieties of chili peppers add a punch to any dish.
Camilla Cheung - Camilla is a Canadian freelance writer currently living on the Central Coast of California. She has a background in teaching and ...
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