Pears are fruits produced and consumed around the world, growing on a tree and harvested in late summer into mid-autumn. The pear tree and shrub are a species of genusPyrus/ˈpaɪrəs/, in the familyRosaceae, bearing the pomaceous fruit of the same name. Several species of pears are valued for their edible fruit and juices, while others are cultivated as trees.
The tree is medium-sized and native to coastal and mildly temperate regions of Europe, North Africa, and Asia. Pear wood is one of the preferred materials in the manufacture of high-quality woodwind instruments and furniture.
About 3,000 known varieties of pears are grown worldwide, which vary in both shape and taste. The fruit is consumed fresh, canned, as juice, dried, or fermented as perry.
Etymology
The word pear is probably from Germanic pera as a loanword of Vulgar Latinpira, the plural of pirum, akin to Greek apios (from Mycenaean ápisos),[1] of Semitic origin (pirâ), meaning "fruit". The adjective pyriform or piriform means pear-shaped.[2] The classical Latin word for a pear tree is pirus;[3]pyrus is an alternate form of this word sometimes used in medieval Latin.[4]
Description
The pear is native to coastal, temperate, and mountainous regions of the Old World, from Western Europe and North Africa east across Asia.[5][6] They are medium-sized trees, reaching up to 20 m tall, often with a tall, narrow crown; a few pear species are shrubby.[7][8]
The leaves are alternately arranged, simple, 2–12 cm (1–4+1⁄2 in) long, glossy green on some species, densely silvery-hairy in some others; leaf shape varies from broad oval to narrow lanceolate.[8] Most pears are deciduous, but one or two species in Southeast Asia are evergreen.[8][9] Some pears are cold-hardy, withstanding temperatures as low as −25 to −40 °C (−13 to −40 °F) in winter, but many grown for agriculture are vulnerable to cold damage.[5][10] Evergreen species only tolerate temperatures down to about −12 °C (10 °F).[11]
The flowers are white, rarely tinted yellow or pink, 2–4 centimetres (1–1+1⁄2 in) diameter, and have five petals, five sepals, and numerous stamens.[8][12] Like that of the related apple, the pear fruit is a pome, in most wild species 1–4 cm (1⁄2–1+1⁄2 in) diameter, but in some cultivated forms up to 18 cm (7 in) long and 9 cm (3+1⁄2 in) broad.[8] 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.[10]
The fruit is a pseudofruit composed of the receptacle or upper end of the flower stalk (the so-called calyx tube) greatly dilated.[8] Enclosed within its cellular flesh is the true fruit: 2–5 'cartilaginous' carpels,[5][13] known colloquially as the "core".[8]
Pears and apples cannot always be distinguished by the form of the fruit;[14] some pears look very much like some apples, e.g. the nashi pear.[7][15]
The word pear, or its equivalent, occurs in all the Celtic languages, while in Slavic and other dialects, differing appellations still referring to the same thing are found—a diversity and multiplicity of nomenclature, which led Alphonse Pyramus de Candolle to infer a very ancient cultivation of the tree from the shores of the Caspian to those of the Atlantic.[19]
The pear was also cultivated by the Romans, who ate the fruits raw or cooked, just like apples.[20]Pliny's Natural History recommended stewing them with honey and noted three dozen varieties. The Roman cookbook De re coquinaria has a recipe for a spiced, stewed-pear patina, or soufflé.[21] Romans also introduced the fruit to Britain.[22]
Pyrus nivalis, which has white down on the undersurface of the leaves, is chiefly used in Europe in the manufacture of perry (see also cider).[19][23][24] Other small-fruited pears, distinguished by their early ripening and globose fruit, may be referred to as P. cordata, a species found wild in southwestern Europe.[25][26][27]
The genus is thought to have originated in present-day Western China[28] in the foothills of the Tian Shan, a mountain range of Central Asia, and to have spread to the north and south along mountain chains, evolving into a diverse group of over 20 widely recognized primary species.[9] The enormous number of varieties of the cultivated European pear (Pyrus communis subsp. communis), are likely derived from one or two wild subspecies (P. c. subsp. pyraster and P. c. subsp. caucasica), widely distributed throughout Europe, and sometimes forming part of the natural vegetation of the forests.[5][8] Court accounts of Henry III of England record pears shipped from La Rochelle-Normande and presented to the king by the sheriffs of the City of London.[29] The French names of pears grown in English medieval gardens suggest that their reputation, at the least, was French; a favoured variety in the accounts was named for Saint Rieul of Senlis, Bishop of Senlis in northern France.[30]
Asian species with medium to large edible fruit include P. pyrifolia, P. ussuriensis, P. × bretschneideri, and P. × sinkiangensis.[8] Small-fruited species, such as Pyrus calleryana, may be used as rootstocks for the cultivated forms.[5][31]
According to Pear Bureau Northwest, about 3,000 known varieties of pears are grown worldwide.[32] The pear is normally propagated by grafting a selected variety onto a rootstock, which may be of a pear or quince variety. Quince rootstocks produce smaller trees, which is often desirable in commercial orchards or domestic gardens. 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.[33]
There are four species which are primarily grown for edible fruit production: the European pearPyrus communis subsp. communis cultivated mainly in Europe and North America, the Chinese white pear (bai li) Pyrus × bretschneideri, the Chinese pear Pyrus ussuriensis, and the Nashi pearPyrus pyrifolia (also known as Asian pear or apple pear), which are grown mainly in eastern Asia.[5] There are thousands of cultivars of these three species.[32] A species grown in western China, P. sinkiangensis, and P. pashia, grown in southern China and south Asia, are also produced to a lesser degree.[5][8]
Other species are used as rootstocks for European and Asian pears and as ornamental trees.[5][31] Pear wood is close-grained and has been used as a specialized timber for fine furniture and making the blocks for woodcuts.[34][35] The Manchurian or Ussurian Pear, Pyrus ussuriensis (which produces unpalatable fruit primarily used for canning) has been crossed with Pyrus communis to breed hardier pear cultivars.[36] The Bradford pear (Pyrus calleryana 'Bradford') is widespread as an ornamental tree in North America, where it has become invasive in regions.[37][38][39] It is also used as a blight-resistant rootstock for Pyrus communis fruit orchards.[36][37] The Willow-leaved pear (Pyrus salicifolia) is grown for its silvery leaves, flowers, and its "weeping" form.[5][40]
The purely decorative cultivar P. salicifolia 'Pendula', with pendulous branches and silvery leaves, has also won the award.[49]
Harvest
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.[8][50] Certain other pears, including Pyrus pyrifolia and P. × bretschneideri, have both climacteric and non-climacteric varieties.[5][51][52]
Pears may be stored at room temperature until ripe.[55] Pears are ripe when the flesh around the stem gives to gentle pressure.[55] Ripe pears are optimally stored refrigerated, uncovered in a single layer, where they have a shelf life of 2 to 3 days.[55]
Pears ripen at room temperature. Ripening is accelerated by the gas ethylene.[56] If pears are placed next to bananas in a fruit bowl, the ethylene emitted by the banana causes the pears to ripen.[57] Refrigeration will slow further ripening. According to Pear Bureau Northwest, most varieties show little color change as they ripen (though the skin on Bartlett pears changes from green to yellow as they ripen).[58]
Uses
Cooking
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, including berries. Fermented pear juice is called perry or pear cider and is made in a way that is similar to how cider is made from apples.[5][10] Perry can be distilled to produce an eau de vie de poire, a colorless, unsweetened fruit brandy.[59]
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 (a sweet variety) and Saint Remy (slightly sour).[63]
Timber
Pear wood is one of the preferred materials in the manufacture of high-quality woodwind instruments and furniture, and was used for making the carved blocks for woodcuts. 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. Lincoln[64] describes it as "a fairly tough, very stable wood... (used for) carving... brushbacks, umbrella handles, measuring instruments such as set squares and T-squares... recorders... violin and guitar fingerboards and piano keys... decorative veneering." Pearwood is the favored wood for architect's rulers because it does not warp. It is similar to the wood of its relative, the apple tree (Malus domestica) and used for many of the same purposes.[64]
Raw pear is 84% water, 15% carbohydrates and contains negligible protein and fat (table). In a 100 g (3+1⁄2 oz) reference amount, raw pear supplies 239 kilojoules (57 kilocalories) of food energy, a moderate amount of dietary fiber, and no micronutrients in significant amounts (table).
Research
A 2019 review found preliminary evidence for the potential of pear consumption to favorably affect cardiovascular health.[67]
Cultural references
Pears grow in the sublime orchard of Alcinous, in the Odyssey vii: "Therein grow trees, tall and luxuriant, pears and pomegranates and apple-trees with their bright fruit, and sweet figs, and luxuriant olives. Of these the fruit perishes not nor fails in winter or in summer, but lasts throughout the year."[68]
The pear tree was an object of particular veneration (as was the walnut) in the tree worship of the Nakh peoples of the North Caucasus – see Vainakh mythology and see also Ingushetia – the best-known of the Vainakh peoples today being the Chechens of Chechnya. Pear and walnut trees were held to be the sacred abodes of beneficent spirits in pre-Islamic Chechen religion and, for this reason, it was forbidden to fell them.[70]
^ abde Candolle, Alphonse (1908). The Origin of Cultivated Plants: The International Scientific Series Volume XLVIII. New York: D. Appleton and Company.
^Grainger, Sally & Grocock, Christopher (2006). Apicius (with an introd. and an Engl. transl.). Blackawton, Totnes: Prospect Books. p. IV.2.35. ISBN978-1-903018-13-2.
^Himmelblau, David M.; Riggs, James B. (2022). Basic principles and calculations in chemical engineering. International series in the physical and chemical engineering sciences (Ninth ed.). Boston: Pearson. ISBN978-0-13-732717-1.
^Stewart, Amy (2013). The drunken botanist: the plants that create the world's great drinks. A New York Times bestseller. Chapel Hill, N.C: Algonquin Books of Chapel Hill. ISBN978-1-61620-046-6.
^National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Food and Nutrition Board; Committee to Review the Dietary Reference Intakes for Sodium and Potassium (2019). Oria, Maria; Harrison, Meghan; Stallings, Virginia A. (eds.). Dietary Reference Intakes for Sodium and Potassium. The National Academies Collection: Reports funded by National Institutes of Health. Washington, DC: National Academies Press (US). ISBN978-0-309-48834-1. PMID30844154. Archived from the original on 9 May 2024. Retrieved 21 June 2024.