Plum


A plum is a fruit of the subgenus Prunus of the genus Prunus. The subgenus is distinguished from other subgenera in the shoots having terminal bud and solitary side buds, the flowers in groups of one to five together on short stems, and the fruit having a groove running down one side and a smooth stone.
Mature plum fruit may have a dusty-white waxy coating that gives them a glaucous appearance. This is an epicuticular wax coating and is known as "wax bloom". Dried plum fruits are called "dried plums" or prunes, although, in many countries, prunes are a distinct type of dried plum having a wrinkled appearance.

History

Plums may have been one of the first fruits domesticated by humans. Three of the most abundant cultivars are not found in the wild, only around human settlements: Prunus domestica has been traced to East European and Caucasian mountains, while Prunus salicina and Prunus simonii originated in Asia. Plum remains have been found in Neolithic age archaeological sites along with olives, grapes and figs. According to Ken Albala, plums originated in Iran.

Etymology and names

The name plum derived from Old English plume or "plum, plum tree," which extended from Germanic language or Middle Dutch, and Latin prūnum, from Ancient Greek προῦμνον, believed to be a loanword from Asia Minor. In the late 18th century, the word, plum, was used to indicate "something desirable", probably in reference to tasty fruit pieces in desserts.

Description

Plums are a diverse group of species. The commercially important plum trees are medium-sized, usually pruned to 5–6 metres height. The tree is of medium hardiness. Without pruning, the trees can reach 12 metres in height and spread across 10 metres. They blossom in different months in different parts of the world; for example, in about January in Taiwan and early April in the United Kingdom.
Fruits are usually of medium size, between 2 and 7 centimetres in diameter, globose to oval. The flesh is firm and juicy. The fruit's peel is smooth, with a natural waxy surface that adheres to the flesh. The plum is a drupe, meaning its fleshy fruit surrounds a single hard seed.

Cultivation and uses

Plum cultivars include:
When it flowers in the early spring, a plum tree will be covered in blossoms, and in a good year approximately 50% of the flowers will be pollinated and become plums. Flowering starts after 80 growing degree days.
If the weather is too dry, the plums will not develop past a certain stage, but will fall from the tree while still tiny, green buds, and if it is unseasonably wet or if the plums are not harvested as soon as they are ripe, the fruit may develop a fungal condition called brown rot. Brown rot is not toxic, and some affected areas can be cut out of the fruit, but unless the rot is caught immediately, the fruit will no longer be edible. Plum is used as a food plant by the larvae of some Lepidoptera, including November moth, willow beauty and short-cloaked moth.
The taste of the plum fruit ranges from sweet to tart; the skin itself may be particularly tart. It is juicy and can be eaten fresh or used in jam-making or other recipes. Plum juice can be fermented into plum wine. In central England, a cider-like alcoholic beverage known as plum jerkum is made from plums. Dried, salted plums are used as a snack, sometimes known as saladito or salao. Various flavors of dried plum are available at Chinese grocers and specialty stores worldwide. They tend to be much drier than the standard prune. Cream, ginseng, spicy, and salty are among the common varieties. Licorice is generally used to intensify the flavor of these plums and is used to make salty plum drinks and toppings for shaved ice or baobing. Pickled plums are another type of preserve available in Asia and international specialty stores. The Japanese variety, called umeboshi, is often used for rice balls, called onigiri or omusubi. The ume, from which umeboshi are made, is more closely related, however, to the apricot than to the plum. In the Balkans, plum is converted into an alcoholic drink named slivovitz . A large number of plums, of the Damson variety, are also grown in Hungary, where they are called szilva and are used to make lekvar, palinka, plum dumplings, and other foods. In Romania, 80% of the plum production is used to create a similar brandy, called țuică.
As with many other members of the rose family, plum kernels contain cyanogenic glycosides, including amygdalin. Prune kernel oil is made from the fleshy inner part of the pit of the plum. Though not available commercially, the wood of plum trees is used by hobbyists and other private woodworkers for musical instruments, knife handles, inlays, and similar small projects.

Species

Plums have many species, and taxonomists differ on the count. Depending on the taxonomist, between 19 and 40 species of plum exist. From this diversity only two species, the hexaploid European plum and the diploid Japanese plum, are of worldwide commercial significance. The origin of these commercially important species is uncertain but may have involved P. cerasifera and possibly P. spinosa as ancestors. Other species of plum variously originated in Europe, Asia and America.
The subgenus Prunus is divided into three sections:
Sect. Prunus – leaves in bud rolled inwards; flowers 1-3 together; fruit smooth, often wax-bloomed
ImageScientific nameCommon NameDistributionCytology
P. cerasiferacherry plum, myrobalan plumSoutheast Europe and Western Asia2n=16,
P. cocomiliaItalian plumAlbania, Croatia, Greece, southern Italy, Montenegro, North Macedonia, Serbia, and western Turkey
P. japonicaJapanese bush cherryCentral China through to the Korean peninsula
P. domestica Europe 2n=16, 48
P. domestica ssp. insititiadamsons, bullacesAsia
P. salicinaChinese plumChina2n=16,
P. simonii China2n=16
P. spinosablackthorn or sloeEurope, western Asia, and locally in northwest Africa2n=4x=32

Sect. Prunocerasus – leaves in bud folded inwards; flowers 3–5 together; fruit smooth, often wax-bloomed
ImageScientific nameCommon NameDistributionCytology
P. alleghaniensisAllegheny plumthe Appalachian Mountains from New York to Kentucky and North Carolina, plus the Lower Peninsula of Michigan
P. americanaAmerican plumNorth America from Saskatchewan and Idaho south to New Mexico and east to Québec, Maine and Florida
P. angustifoliaChickasaw plumFlorida west as far as New Mexico and California
P. gracilisOklahoma plumAlabama, Arkansas, Colorado, Kansas, Louisiana, New Mexico, Oklahoma and Texas
P. havardiiHavard's plumwestern Texas in the United States and to northern Chihuahua across the Río Grande in Mexico
P. hortulanaHortulan plumArkansas, Iowa, Illinois, Indiana, Kansas, Kentucky, Massachusetts, Maryland, Missouri, Nebraska, Ohio, Oklahoma, Tennessee, Texas, Virginia, West Virginia
P. maritimaBeach plumEast Coast of the United States, from Maine south to Maryland
P. mexicanaMexican plumcentral United States and Northern Mexico
P. murrayanaMurray's plumTexas-
P. nigraCanada plum, Black plumeastern North America from Nova Scotia west to Minnesota and southeastern Manitoba, and south as far as Connecticut, Illinois, and Iowa
P. × orthosepala southern and central United States
P. reverchoniiThicket plum
P. rivularisRiver plum, Creek plum,Wildgoose plumCalifornia, Arkansas, southern Illinois, south-eastern Kansas, Kentucky, northern Louisiana, Mississippi, Missouri, south-western Ohio, Oklahoma, Tennessee, and Texas
P. subcordataKlamath, Oregon, or Sierra plumCalifornia and western and southern Oregon
P. texanaTexas plum, Sand plum, Peachbush plumcentral and western Texas-
P. umbellataHog plum, Flatwoods plum, Sloe plumUnited States from Virginia, south to Florida, and west to Texas

Sect. Armeniaca – leaves in bud rolled inwards; flowers very short-stalked; fruit velvety; treated as a distinct subgenus by some authors
ImageScientific nameCommon NameDistributionCytology
P. armeniacaapricotAsia2n=16
P. brigantinaBriançon apricot, marmot plumEurope
P. mandshuricaManchurian apricot and Scout apricotnortheast China, Korea, and Manchuria
P. mumeChinese plum, Japanese apricotWestern Asia
P. sibiricaSiberian apricoteastern China, Japan, Korea, Mongolia, and eastern Siberia.

In certain parts of the world, some fruits are called plums and are quite different from fruits known as plums in Europe or the Americas. For example, marian plums are popular in Thailand, Malaysia and Indonesia, otherwise also known as gandaria, plum mango, ma-praang, ma-yong, ramania, kundang, rembunia or setar. Another example is the loquat, also known as Japanese plum and Japanese medlar, as well as nispero, bibassier and wollmispel elsewhere. In South Asia and Southeast Asia, Jambul, a fruit from tropical tree in family Myrtaceae, is similarly sometimes referred to 'damson plums', and it is different from damson plums found in Europe and Americas. Jambul is also called as Java plum, Malabar plum, Jaman, Jamun, Jamblang, Jiwat, Salam, Duhat, Koeli, Jambuláo or Koriang.

Production

In 2016, global production of plums and sloes was 12.1 million tonnes, led by China with 55% of the world total. Other major producers were Romania, Serbia, and the United States.

Nutrition

Raw plums are 87% water, 11% carbohydrates, 1% protein, and less than 1% fat. In a reference serving, raw plums supply of food energy and are a moderate source only of vitamin C, with no other nutrients in significant content.