A plum is a fruit of the subgenus Prunus of the genus Prunus. The subgenus is distinguished from other subgenera (peaches, cherries, bird cherries, etc.) in the shoots having terminal bud and solitary side buds (not clustered), 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 (or pit).
|A plum; whole and split|
|Black Amber Plum|
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 American English, prunes are a distinct type of plum, and may have pre-dated the fruits now commonly known as plums.
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.
Etymology and namesEdit
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 usesEdit
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.
As with many other members of the rose family, plum seeds contain cyanogenic glycosides, including amygdalin. These substances are capable of decomposing into a sugar molecule and hydrogen cyanide gas. While plum seeds are not the most toxic within the rose family (the bitter almond is the most toxic), large doses of these chemicals from any source are hazardous to human health. On the other hand, plums are considered a source of phytochemical compounds with beneficial effects on health.
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.
Plum cultivars in use today include:
- Damson (purple or black skin, green flesh, clingstone, astringent)
- Greengage (firm, green flesh and skin even when ripe)
- Mirabelle (dark yellow, predominantly grown in northeast France)
- Satsuma plum (firm red flesh with a red skin)
- Victoria (yellow flesh with a red or mottled skin)
- Yellowgage or golden plum (similar to greengage, but yellow)
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 very small 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 Serbian plum (Serbian: шљива / šljiva) is the third most produced in the world. In the Balkans, plum is converted into an alcoholic drink named slivovitz (plum brandy) (Serbian: шљивовица / šljivovica).
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 (a plum paste jam), palinka (traditional fruit brandy), plum dumplings, and other foods. The region of Szabolcs-Szatmár, in the northeastern part of the country near the borders with Ukraine and Romania, is a major producer of plums.
The plum is commonly used in China, Yunnan area, to produce a local plum wine with a smooth, sweet, fruity taste and approximately 12% alcohol by volume.
|Source: UN Food & Agriculture Organization|
Plum has 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 (Prunus domestica) and the diploid Japanese plum (Prunus salicina and hybrids), 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.
|Nutritional value per 100 g (3.5 oz)|
|Energy||192 kJ (46 kcal)|
|Dietary fiber||1.4 g|
|Vitamin A equiv.||
|Pantothenic acid (B5)||
|Percentages are roughly approximated using US recommendations for adults.
Source: USDA Nutrient Database
The subgenus Prunus is divided into three sections:
- Sect. Prunus (Old World plums) – leaves in bud rolled inwards; flowers 1-3 together; fruit smooth, often wax-bloomed
- Sect. Prunocerasus (New World plums) – leaves in bud folded inwards; flowers 3–5 together; fruit smooth, often wax-bloomed
- P. alleghaniensis (Allegheny plum)
- P. americana (American plum)
- P. angustifolia (Chickasaw plum)
- P. gracilis (Oklahoma plum)
- P. havardii (Havard's plum)
- P. hortulana (Hortulan plum)
- P. maritima (Beach plum)
- P. mexicana (Mexican plum)
- P. munsoniana (Wildgoose plum)
- P. murrayana (Murray's plum)
- P. nigra (Canada plum, Black plum)
- P. × orthosepala (P. americana × P. angustifolia)
- P. reverchonii (Thicket plum)
- P. rivularis (River plum, Creek plum)
- P. subcordata (Klamath, Oregon, or Sierra plum)
- P. texana (Texas plum, Sand plum, Peachbush plum)
- P. umbellata (Hog plum, Flatwoods plum, Sloe plum)
- Sect. Armeniaca (apricots) – leaves in bud rolled inwards; flowers very short-stalked; fruit velvety; treated as a distinct subgenus by some authors
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 Myrtaceae family, 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.
Raw plums are 87% water, 11% carbohydrates, 1% protein, and less than 1% fat (table). In a 100 gram amount, raw plums supply 46 Calories and are a moderate source only of vitamin C (12% Daily Value), with no other nutrients in significant content (table).
- D. Potter; T. Eriksson; R. C. Evans; S. Oh; J. E. E. Smedmark; D. R. Morgan; M. Kerr; K. R. Robson; M. Arsenault; T. A. Dickinson; C. S. Campbell (2007). "Phylogeny and classification of Rosaceae" (PDF). Plant Systematics and Evolution. 266 (1–2): 5–43. doi:10.1007/s00606-007-0539-9. Note that this publication pre-dates the 2011 International Botanical Congress which mandates that the combined subfamily referred to in the paper as Spiraeoideae must be called Amygdaloideae.
- Oxford English Dictionary. Oxford University Press. ISBN 0199563837.
- Jules Janick, ed. (1998). Horticultural Reviews (Volume 23). Wiley. ISBN 978-0471254454.
- Jules Janick (2005). "The origins of fruits, fruit growing and fruit breeding" (PDF). Purdue University.
- Spangenberg; et al. (January 2006). "Chemical analyses of organic residues in archaeological pottery from Arbon Bleiche". Journal of Archaeological Science. 33 (1): 1–13. doi:10.1016/j.jas.2005.05.013.
- "Plum". Etymology Online Dictionary; Douglas Harper. 2017. Retrieved 12 June 2017.
- "Plum, prune, European type". Purdue University. 1999.
- "Prunus domestica Plum, European plum PFAF Plant Database". pfaf.org.
- Burrows, G.E.; Tyrl, R.J. (2012). "Rosaceae Juss.". Toxic Plants of North America. Wiley-Blackwell. pp. 1064–1094.
- González-Flores D, Velardo B, Garrido M, González-Gómez D, Lozano M, Ayuso M.C, Barriga C, Paredes S.D, Rodríguez A.B. (2011). "Ingestion of Japanese plums (Prunus salicina Lindl. cv. Crimson Globe) increases the urinary 6-sulfatoxymelatonin and total antioxidant capacity levels in young, middle-aged and elderly humans: Nutritional and functional characterization of their content". Journal of Food and Nutrition Research 50(4): 229-236.
- "Plum". The Wood Database.
- Crowell and Guymon (1973). "Aroma Constituents of Plum Brandy". American Journal of Enology. 24 (4): 159–165.
- Jan Velíšek; František Pudil; Jiří Davídek; Vladislav Kubelka (1982). "The neutral volatile components of Czechoslovak plum brandy". Zeitschrift für Lebensmittel-Untersuchung und -Forschung A. 174 (6): 463–466. doi:10.1007/BF01042726.
- "Plum production in 2014; Crops/Regions/World/Production Quantity by pick lists". UN Food & Agriculture Organization, Statistics Division. 2016. Retrieved 12 June 2017.
- Bruce L. Topp; Dougal M. Russell; Michael Neumüller; Marco A. Dalbó; Weisheng Liu (2012). Plum (Handbook of Plant Breeding). 8, part 3. pp. 571–621. doi:10.1007/978-1-4419-0763-9_15.
- "Prunus simonii in Flora of China @ efloras.org". efloras.org.
- "Under-Utilized Tropical Fruits of Thailand (see Part 1, section 3)". FAO, United Nations. 2001.
- "Japanese Plum - Loquat". University of Florida, Nassau County Extension, Horticulture. 2006. Archived from the original on 23 July 2008.
- J. Morton (1987). "Loquat". University of Purdue.
- "Jambolan". Purdue University. 2006.