Sweet peppers, also known as bell peppers, are green when immature and red, yellow, or purple when ripe. Hot peppers are distinguished from sweet peppers by their shape (they are longer and skinnier) and by their burning taste. Like bell peppers, jalapenos, chili peppers, and cayennes will turn red as they ripen.

Sweet peppers with the skin on have about 1 g dietary fiber per pepper (insoluble cellulose and lignin in the peel, soluble pectin in the flesh). Peppers have moderate to high amounts if vitamin A derived from yellow carotenes (including beta-carotene). The amount of vitamin A increases as the pepper ripens; sweet red bell peppers have nearly 10 times as much vitamin A as green ones. Peppers are also a good source of vitamin C.

Fresh peppers hold their nutrients well, even at room temperature. For example, green peppers stored at room temperature retained 85 percent of their vitamin C after 48 hours.

Peppers are members of the nightshade family, Solanacea. Other members of this family are eggplant, potatoes, tomatoes and some mushrooms. Nightshade plants produce natural toxins called glycoalkaloids. The toxin in pepper is solanine. It is estimated that an adult would have to eat 4.5 pounds of peppers at one sitting to get a toxic amount of this glycoalkaloid.

Preparing This Food

Sweet bell peppers. Wash the peppers under cold running water, slice, and remove the seeds and membranes (which are irritating). If you plan to cook the peppers, peel them; the skin will otherwise curl up into a hard, unpalatable strip. Immerse the pepper in hot water, then lift it out and plunge it into cold water. The hot water bath damages a layer of cells under the skin so that the skin is very easy to peel off. Roasting the peppers produces the same result.

Hot peppers. NEVER HANDLE ANY VARIETY OF HOT PEPPERS WITH YOUR BARE HANDS. Hot peppers contain large amounts of the naturally occurring irritants capsaicin (pronounced cap-say-i-sun), nordyhydrocapsaicin, and dihydrocapsaicin. These chemicals cause pain by latching on to special sites called receptors on the surface of nerve cells, opening small channels in the cells that permit calcium particles to flood in. The calcium particles trigger the pain reaction. Exposure to high temperatures, like a bum, produces the same effect.

Capsaicins irritate the lining of your mouth and esophagus (which is why they cause heartburn). They can burn unprotected skin and mucous membranes. Capsaicins dissolve in milk fat and alcohol, but not water. They cannot simply be washed off your hands.

NOTE: Capsaicin extracted from hot peppers and applied to the skin as the active ingredient in a cream or ointment is an effective over-the-counter pain remedy. In addition, in a 1991 study at the University of Florence (Italy), 39 men and women suffering from cluster headaches (a form of migraine) obtained relief by squirting a capsaicin-containing solution into the nostril on the headache side of the face. WARNING: THE CAPSAICLN USED TO RELIEVE PAIN IS A

PURIFIED, MEDICAL-GRADE PRODUCT EXTRACTED FROM PEPPERS. HOT PEPPERS THEMSELVES DO NOT RELIEVE PAIN AND SHOULD NEVER BE. APPLIED TO SKIN OR MUCOUS MEMBRANES.

What Happens When You Cook Pepper

Chlorophyll, the pigment that makes green vegetables green, is sensitive to acids. When you heat green peppers, the chlorophyll in the flesh will react chemically with acids in the pepper or in the cooking water, forming pheophytin, which is brown. The pheophytin makes a cooked pepper olive-drab or (if the pepper has a lot of yellow carotenes) bronze.

To keep cooked green peppers green, you have to keep the chlorophyll from reacting with acids. One way to do this is to cook peppers in a large quantity of water (which dilutes the acids), but this increases the loss of vitamin C. A second alternative is to cook them in a pot with the lid off so that the volatile acids float off into the air. Or you can stir-fry the peppers, cooking them so East that there is almost no time for the chlorophyll/acid reaction to occur.

When long cooking is inevitable, as with stuffed sweet green peppers, the only remedy is to smother the peppers in sauce so that it doesn't matter what color the peppers are. (Red and yellow peppers won't fade; their carotenoid pigments are impervious to heat.)

Because vitamin C is sensitive to heat, cooked peppers have less than fresh peppers. But peppers have so much vitamin C to begin with that even cooked peppers are a good source of this nutrient.