Broccoli (Brassica oleracea var. italica) is an edible green plant in the cabbage family (family Brassicaceae, genus Brassica) whose large flowering head, stalk and small associated leaves are eaten as a vegetable. Broccoli is classified in the Italica cultivar group of the species Brassica oleracea. Broccoli has large flower heads, or florets, usually dark green, arranged in a tree-like structure branching out from a thick stalk, which is usually light green. The mass of flower heads is surrounded by leaves. Broccoli resembles cauliflower, which is a different but closely related cultivar group of the same Brassica species.
Rapini, sometimes called "broccoli rabe", is a distinct species from broccoli, forming similar but smaller heads, and is actually a type of turnip (Brassica rapa).[4]
Taxonomy
Brassica oleracea var. italica was described in 1794 by Joseph Jakob von Plenck in Icones Plantarum Medicinalium 6:29, t. 534.[5] Like all the other brassicas, broccoli was developed from the wild cabbage (Brassica oleracea var. oleracea), also called colewort or field cabbage.
Etymology
The word broccoli, first used in the 17th century, comes from the Italian plural of broccolo, which means "the flowering crest of a cabbage", and is the diminutive form of brocco, meaning "small nail" or "sprout".[6]
History
Broccoli resulted from the breeding of landraceBrassica crops in the northern Mediterranean starting in about the sixth century BCE.[7] Broccoli has its origins in primitive cultivars grown in the Roman Empire and was most likely improved via artificial selection in the southern Italian Peninsula or in Sicily.[8][9][10] Broccoli was spread to northern Europe by the 18th century and brought to North America in the 19th century by Italian immigrants.[9] After the Second World War, the breeding of the United States and JapaneseF1 hybrids increased yields, quality, growth speed, and regional adaptation, which produced the cultivars commonly grown since then: 'Premium Crop', 'Packman', and 'Marathon'.[9]
Description
Broccoli is an annual plant which can grow up to 60–90 cm (20–40 in) tall.[11]
Broccoli is very similar to cauliflower, but unlike it, its floral buds are well-formed and clearly visible.[further explanation needed] The inflorescence grows at the end of a central, thick stem and is dark green. Violet, yellow or even white heads have been created, but these varieties are rare. The flowers are yellow with four petals.
The growth season for broccoli is 14–15 weeks. Broccoli is collected by hand immediately after the head is fully formed yet the flowers are still in their bud stage. The plant develops numerous little "heads" from the lateral shoots which can be harvested later.
Varieties
There are three commonly grown types of broccoli.[9] The most familiar is Calabrese broccoli, often referred to simply as "broccoli", named after Calabria in Italy. It has large 10-to-20-centimetre (4–8 in) green heads and thick stalks. It is a cool-season annual crop. Sprouting broccoli (white or purple) has a larger number of heads with many thin stalks.[12]Purple cauliflower or violet cauliflower is a type of broccoli grown in Europe and North America. It has a head shaped like cauliflower but consists of many tiny flower buds. It sometimes, but not always, has a purple cast to the tips of the flower buds. Purple cauliflower may also be white, red, green, or other colors.[13]
Beneforté is a variety of broccoli containing 2–3 times more glucoraphanin and produced by crossing broccoli with a wild Brassica variety, Brassica oleracea var villosa.[14]
Other cultivar groups of Brassica oleracea include cabbage (Capitata Group), cauliflower and Romanesco broccoli (Botrytis Group), kale (Acephala Group), collard (Viridis Group), kohlrabi (Gongylodes Group), Brussels sprouts (Gemmifera Group), and kai-lan (Alboglabra Group).[15] As these groups are the same species, they readily hybridize: for example, broccolini or "Tenderstem broccoli" is a cross between broccoli and kai-lan.[16] Broccoli cultivars form the genetic basis of the "tropical cauliflowers" commonly grown in South and Southeastern Asia, although they produce a more cauliflower-like head in warmer conditions.[17][9]
The majority of broccoli cultivars are cool-weather crops that do poorly in hot summer weather. Broccoli grows best when exposed to an average daily temperature between 18 and 23 °C (64 and 73 °F).[19][20] When the cluster of flowers, also referred to as a "head" of broccoli, appears in the center of the plant, the cluster is generally green. Garden pruners or shears are used to cut the head about 25 mm (1 in) from the tip. Broccoli should be harvested before the flowers on the head bloom bright yellow.[21] Broccoli cannot be harvested using machines, but rather is hand-harvested.[22]
Production
In 2021, global production of broccoli (combined for production reports with cauliflowers) was 26 million tonnes, with China and India together accounting for 72% of the world total.[18] Secondary producers, each having about one million tonnes or less annually, were the United States, Spain, and Mexico (table).
In the United States, broccoli is grown year-round in California – which produced 92% of the crop nationally – with 95% of the total crop produced for fresh sales in 2018.[23]
Raw broccoli is 89% water, 7% carbohydrates, 3% protein, and contains negligible fat (table). A 100-gram (3+1⁄2-ounce) reference amount of raw broccoli provides 141 kilojoules (34 kilocalories) of food energy and is a rich source (20% or higher of the Daily Value, DV) of vitamin C (107% DV) and vitamin K (97% DV) (table). Raw broccoli also contains moderate amounts (10–19% DV) of several B vitamins and the dietary mineralmanganese, whereas other micronutrients are low in content (less than 10% DV). Broccoli contains the dietary carotenoid, beta-carotene.[26]
Boiling substantially reduces the levels of broccoli glucosinolates, while other cooking methods, such as steaming, microwaving, and stir-frying, have no significant effect on glucosinolate levels.[3]
Taste
The perceived bitterness of cruciferous vegetables, such as broccoli, results from glucosinolates and their hydrolysis products, particularly isothiocyanates and other sulfur-containing compounds.[27] Preliminary research indicates that genetic inheritance through the gene TAS2R38 may be responsible in part for bitter taste perception in broccoli.[28]
Pests
The larvae of Pieris rapae, also known as the "small white" butterfly, are a common pest in broccoli and were mostly introduced accidentally to North America, Australia and New Zealand.[29]
Additional pests common to broccoli production include:[30]
^Branca, Ferdinando (2008), Prohens, Jaime; Nuez, Fernando (eds.), "Cauliflower and Broccoli", Vegetables I: Asteraceae, Brassicaceae, Chenopodicaceae, and Cucurbitaceae, Handbook of Plant Breeding, vol. 1, New York, NY: Springer, pp. 151–186, doi:10.1007/978-0-387-30443-4_5, ISBN978-0-387-30443-4
^Branham, Sandra E.; Stansell, Zachary J.; Couillard, David M.; Farnham, Mark W. (1 March 2017). "Quantitative trait loci mapping of heat tolerance in broccoli (Brassica oleracea var. italica) using genotyping-by-sequencing". Theoretical and Applied Genetics. 130 (3): 529–538. doi:10.1007/s00122-016-2832-x. ISSN1432-2242. PMID27900399. S2CID2361874.
^"Broccoli production". Pennsylvania State University, Extension Service. 20 June 2005. Archived from the original on 19 February 2021. Retrieved 10 February 2021.
^"Broccoli". Agricultural Marketing Resource Center, US Department of Agriculture. 1 June 2018. Archived from the original on 1 July 2019. Retrieved 27 June 2019.
^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.
^Heitzman, J. Richard; Heitzman, Joan E. (1996). Love, Kathy; Larsen, LuAnne (eds.). Butterflies and moths of Missouri. Rathert, Jim (principal photographer). Jefferson City, MO: Missouri Dept. of Conservation. ISBN1-887247-06-8.