What makes peppers hot?
Most species of Capsicum contain capsaicin (methyl vanillyl nonenamide), a chemical that produces a strong burning sensation in the mouth. Capsaicin is mainly present in the pepper’s placenta, the white “ribs” that run down the middle and along the sides of a pepper, as well as in the seeds, and it is also unevenly distributed throughout the flesh. The amount of capsaicin in peppers is highly variable and is dependent on genetics. Sometimes, both sweet and hot cultivars can be found within a type, and even in the one cultivar cool weather, excess water and nitrogen will increase sweetness, while stress adds pungency. The only pepper without capsaicin is the bell pepper. In hot peppers you can see the capsaicin in the form of a shiny yellow substance on the placenta. A hot pepper can be made considerably less hot by removing the placenta.
