Pears
Pears are high in dietary fiber, with insoluble cellulose in the skin, lignin in the tiny gritty particles in the fruit flesh, plus soluble pectins. They are high in sugars and have moderate amounts of vitamin C, concentrated in the skin. Their most important mineral is potassium.
One six-ounce fresh pear, with skin, has 5.5 g dietary fiber and 7.5 mg vitamin C (10 percent of the RDA for a woman, 8 percent of the RDA for a man).
Like apple seeds and peach pits, the seeds of pears contain amygdalin, a cyanide/sugar compound that breaks down into hydrogen cyanide in your stomach. Accidentally swallowing a pear seed is not necessarily hazardous for an adult, but there have been reports of serious poisoning among people who have eaten several apple seeds (see apples).
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Fresh and ripe, with the skin (for the extra fiber and vitamin C).
Look for: Large, firm, ripe pears. Most fruit and vegetables get softer after they are picked because their pectic enzymes begin to dissolve the pectin in their cell walls. With pears, this reaction occurs if the pear is left on the tree to ripen, which is why tree-ripened pears sometimes taste mushy. The best-tasting pears are ones that are picked immature and allowed to ripen in storage or on your grocer’s shelf.
Look for bright, clear-colored pears. Anjou pears are yellow to green (with some russet shades) and have a bland, buttery flesh. Bartletts are clear golden or yellow with a reddish blush and sweet, juicy flesh. Boscs are russet, sweet and juicy. Round Comice pears have a yellow green skin and fine, juicy flesh. Red Seckel pears are firm and aromatic. Anjou, Bartlett, and Bosc are good eating and cooking pears; Comice and Seckel pears are for eating.
Avoid: Cut, shriveled, or bruised pears. They are probably discolored inside.
Store pears at room temperature for a few days if they are not fully ripe when you buy them. Pears ripen from inside out, so you should never let a pear ripen until it is really soft on the surface. A ripe pear will yield when you press it lightly with your palm.
Do not store pears in sealed plastic bags either in or out of the refrigerator. Without oxygen circulating freely around the pear, the fruit will begin to “breathe” internally, creating compounds that turn the core brown and make brownish spots under the skin.
Handle pears with care; never peel or slice them until you are ready to use them. When you bruise a pear or slice into it, you tear its cells, releasing polyphenoloxidase, an enzyme that hastens the oxidation of phenols in the fruit, producing clumps of brownish compounds that darken the pear’s flesh.
You can slow this natural reaction (but not stop it completely) by chilling the pears, brushing the cut surface with an acid solution (lemon juice and water, vinegar and water), or mixing the peeled, sliced fruit into a fresh fruit salad with citrus fruits full of vitamin C, a natural antioxidant.
Like other fruits and vegetables, pears have cell walls made of cellulose, hemicellulose, and pectic substances. As the fruit cooks and its pectins dissolve, it gets softer. But no amount of cooking will dissolve the lignin particles in the pear flesh. In fact, the softer the pear, the easier it is to taste the lignin particles.
Drying. Dried pears have more fiber and potassium but less vitamin C than fresh pears. One-half of a dried pear (2 ounces) has 5.7 g fiber, 405 mg potassium, and 5.32 mg vitamin C. Fresh pears are sometimes treated with sulfur compounds such as sulfur dioxide to inactivate polyphenoloxidase and keep the pears from darkening when they are exposed to air while drying. People who are sensitive to sulfites may suffer serious allergic reactions, including anaphylactic shock, if they eat these treated dried pears.
Sealed packages of dried pears may be stored at room temperature for up to six months. Once the package is opened, the pears should be refrigerated in a tightly closed container that will protect them from air and moisture.
Potassium replacement. Pears are a moderately good source of potassium. One 3.5-ounce Bartlett has about as much the potassium as three ounces of fresh orange juice. Foods rich in potassium are sometimes prescribed for people taking diuretics that lower the body’s level of potassium, which is excreted in urine. However, there is some question as to whether potassium gluconate, the form of potassium found in pears and other fresh fruit, is as useful to the body as potassium citrate and potassium chloride, the forms of potassium given to laboratory animals in the experiments which showed that people taking diuretic drugs would benefit from potassium supplements.
Sulfite allergies. See How other kinds of processing affect this food.
