The pear is a fruit tree of genus Pyrus and also the name of the tree's edible pomaceous fruit. The pear is classified in subtribe Pyrinae within tribe Pyreae and is a perennial. The apple (Malus domestica), which it resembles in floral structure, is also a member of this subcategory.
Pears are native to coastal and mildly temperate regions of the Old World, from western Europe and north Africa east right across Asia. They are medium sized trees, reaching 10–17 m tall, often with a tall, narrow crown; a few species are shrubby. The leaves are alternately arranged, simple, 2–12 cm long, glossy green on some species, densely silvery-hairy in some others; leaf shape varies from broad oval to narrow lanceolate. Most pears are deciduous, but one or two species in southeast Asia are evergreen. Most are cold-hardy, withstanding temperatures between −25 °C and −40 °C in winter, except for the evergreen species, which only tolerate temperatures down to about −15 °C. The flowers are white, rarely tinted yellow or pink, 2–4 cm diameter, and have five petals. Like that of the related apple, the pear fruit is a pome, in most wild species 1–4 cm diameter, but in some cultivated forms up to 18 cm long and 8 cm broad; the shape varies in most species from oblate or globose, to the classic pyriform 'pear-shape' of the European Pear with an elongated basal portion and a bulbous end.
The fruit is composed of the receptacle or upper end of the flower-stalk (the so-called calyx tube) greatly dilated. Enclosed within its cellular flesh is the true fruit: five cartilaginous carpels, known colloquially as the "core". From the upper rim of the receptacle are given off the five sepals[vague], the five petals, and the very numerous stamens.
The pear is very similar to the apple in cultivation, propagation and pollination. The pear and the apple are also related to the quince.
Pears and apples cannot always be distinguished by the form of the fruit; some pears look very much like some apples. One major difference is that the flesh of pear fruit contains stone cells (also called "grit"). Pear trees and apple trees do have several visible differences.
According to Pear Bureau Northwest, there are about 3000 known varieties of pears grown worldwide. In the United States only 10 heirloom varieties are widely recognized: Green Bartlett, Red Bartlett, Bosc, Green Anjou, Red Anjou, Comice, Forelle, Seckel, Concorde, and Starkrimson.
The pear is frequently raised by sowing the pips (seeds) of ordinary cultivated or of wild kinds, these forming what are known as free or pear stocks, on which the choicer varieties are grafted for increase. Both quince and clonally-produced pear rootstocks are also used for Pyrus communis orchards. For new varieties the flowers can be cross-bred to preserve or combine desirable traits. The fruit of the pear is produced on spurs, which appear on shoots more than one year old.
Summer and autumn cultivars of Pyrus communis, being Climacteric fruits are gathered before they are fully ripe, while they are still green, but snap off when lifted. In the case of the 'Passe Crassane', long the favored winter pear in France, the crop should is traditionally gathered at three different times: the first a fortnight or more before it is ripe, the second a week or ten days after that, and the third when fully ripe. The first gathering will come into eating last, and thus the season of the fruit may be considerably prolonged. Nashi pears are allowed to ripen on the tree.
Pears may be stored at room temperature until ripe. Pears are ripe when flesh around stem gives to gentle pressure. Ripe pears are optimally stored refrigerated, uncovered in a single layer, where they have a shelf life of 2 to 3 days.
Pears are consumed fresh, canned, as juice, and dried. The juice can also be used in jellies and jams, usually in combination with other fruits or berries. Fermented pear juice is called perry or pear cider.
Pears ripen at room temperature. They will ripen faster if placed next to bananas in a fruit bowl. Refrigeration will slow further ripening. Pear Bureau Northwest offers tips on ripening and judging ripeness: While the skin on Bartlett pears changes from green to yellow as they ripen, most varieties show little color change as they ripen. Because pears ripen from the inside out, the best way to judge ripeness is to "Check the Neck." To Check the Neck for ripeness, apply gentle thumb pressure to the neck, or stem end of the pear. If it yields to gentle pressure, then the pear is ripe, sweet, and juicy. If it is firm, leave pear at room temperature and Check the Neck daily for ripeness.
The culinary or cooking pear is green but dry and hard and only edible after several hours of cooking. Two Dutch cultivars are "Gieser Wildeman" and "Saint Remy". They are traditionally stewed in wine with spices and served both warm and cold.
Pear wood is one of the preferred materials in the manufacture of high-quality woodwind instruments and furniture. It is also used for wood carving, and as a firewood to produce aromatic smoke for smoking meat or tobacco. Pear wood is valued for kitchen spoons, scoops and stirrers, as it does not contaminate food with color, flavor or smell and resists warping and splintering despite repeated soaking and drying cycles. Pear leaves were smoked in Europe before tobacco was introduced.
Pears are less allergenic than many other fruits, and pear juice is therefore sometimes used as the first juice introduced to infants. However, caution is recommended for all fruit juice consumption by infants as studies have suggested a link between excessive fruit juice consumption and reduced nutrient intake as well as a tendency towards obesity. Pears are low in salicylates and benzoates and are therefore recommended in exclusion diets for allergy sufferers. Along with lamb and rice, pears may form part of the strictest exclusion diet for allergy sufferers.
Pears can be useful in treating inflammation of mucous membranes, colitis, chronic gallbladder disorders, arthritis, and gout. Pears can also be beneficial in lowering high blood pressure, controlling blood cholesterol levels, and increasing urine acidity.
In ancient Greece, pears were used to treat nausea. Most of the fiber is insoluble, making pears a good laxative. The gritty fiber content may cut down on the number of cancerous colon polyps. Most of the vitamin C, as well as the dietary fiber, is contained within the skin of the fruit.
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