Peppers are a hot topic these days, with Mexican and Southwestern cuisines being so popular. There are over 20 species of peppers. Some are hot, some are mild.

Most peppers grown in the United States are of the species Capsicum annuum, a small shrub-like plant of the nightshade family. How hot or pungent peppers are depends on the amount of seven chemical compounds called capsaicinoids. These are also referred to as capsaicin. The human tongue can detect this strong flavor even at one part per million. And although they are produced in the membranes that join the seeds to the plants, the seeds also absorb this chemical.

There are two ways to test the strength of the flavor of hot peppers. One way is to use the Scoville Organoleptic Test. This test requires trained testers to rate hotness on a numerical scale. The other way is to measure the amount of capsaicinoids present in chilies.

The table below shows the heat index of various common varieties along with their characteristic look and/or use. In general, the size of a hot pepper indicates its spiciness. The hotter types tend to be smaller, and milder ones are longer. Also ‘green-turning-red’ types are hotter than ‘yellow-turning-red’ types.

Hot peppers can cause severe skin irritation. Wear rubber or plastic gloves while handling and preparing them. Or if you use your bare hands, wash them thoroughly with soap and warm water. Keep the peppers and anything that touches them away from the face and eyes. Even the steam from cooking potently hot peppers can irritate the skin.

Source: Salsa Recipe for Canning, Pacific Northwest Extension Publication 395 – 1992