Fruit of the Week - Banana

Peeled, whole, and longitudinal section

Banana is the common name for herbaceous plants of the genus Musa and for the fruit they produce. Bananas come in a variety of sizes and colors when ripe, including yellow, purple, and red.

Almost all modern edible parthenocarpic bananas come from the two wild species – Musa acuminata and Musa balbisiana. The scientific names of bananas are Musa acuminata, Musa balbisiana or hybrids Musa acuminata × balbisiana, depending on their genomic constitution. The old scientific names Musa sapientum and Musa paradisiaca are no longer used.

Banana is also used to describe Enset and Fe'i bananas, neither of which belong to the aforementioned species. Enset bananas belong to the genus Ensete while the taxonomy of Fe'i-type cultivars is uncertain.

In popular culture and commerce, "banana" usually refers to soft, sweet "dessert" bananas. By contrast, Musa cultivars with firmer, starchier fruit are called plantains or "cooking bananas". The distinction is purely arbitrary and the terms 'plantain' and 'banana' are sometimes interchangeable depending on their usage.

They are native to tropical South and Southeast Asia, and are likely to have been first domesticated in Papua New Guinea. Today, they are cultivated throughout the tropics. They are grown in at least 107 countries, primarily for their fruit, and to a lesser extent to make fiber, banana wine and as ornamental plants.

The banana plant is the largest herbaceous flowering plant. The plants are normally tall and fairly sturdy and are often mistaken for trees, but their main or upright stem is actually a pseudostem that grows 20 to 24.9 ft tall, growing from a corm. Each pseudostem can produce a single bunch of bananas. After fruiting, the pseudostem dies, but offshoots may develop from the base of the plant. Many varieties of bananas are perennial.

Leaves are spirally arranged and may grow 8.9 ft long and 2.0 ft wide. They are easily torn by the wind, resulting in the familiar frond look.

Each pseudostem normally produces a single inflorescence, also known as the banana heart. (More are sometimes produced; an exceptional plant in the Philippines produced five.) The inflorescence contains many bracts (sometimes incorrectly called petals) between rows of flowers. The female flowers (which can develop into fruit) appear in rows further up the stem from the rows of male flowers. The ovary is inferior, meaning that the tiny petals and other flower parts appear at the tip of the ovary.

The banana fruits develop from the banana heart, in a large hanging cluster, made up of tiers (called hands), with up to 20 fruit to a tier. The hanging cluster is known as a bunch, comprising 3–20 tiers, or commercially as a "banana stem", and can weigh from 66–110 lb. In common usage, bunch applies to part of a tier containing 3–10 adjacent fruits.

Individual banana fruits (commonly known as a banana or 'finger') average 0.28 lb, of which approximately 75% is water and 25% dry matter. There is a protective outer layer (a peel or skin) with numerous long, thin strings (the phloem bundles), which run lengthwise between the skin and the edible inner portion. The inner part of the common yellow dessert variety splits easily lengthwise into three sections that correspond to the inner portions of the three carpels.

The fruit has been described as a "leathery berry". In cultivated varieties, the seeds are diminished nearly to non-existence; their remnants are tiny black specks in the interior of the fruit. Bananas grow pointing up, not hanging down.

Bananas are naturally slightly radioactive, more so than most other fruits, because of their high potassium content, and the small amounts of the isotope potassium-40 found in naturally occurring potassium. Proponents of nuclear power sometimes refer to the banana equivalent dose of radiation to support their arguments.

In the 15th and 16th century, Portuguese colonists started banana plantations in the Atlantic Islands, Brazil, and western Africa. North Americans began consuming bananas on a small scale at very high prices shortly after the Civil War, though it was only in the 1880s that it became more widespread. As late as the Victorian Era, bananas were not widely known in Europe, although they were available.[30] Jules Verne introduces bananas to his readers with detailed descriptions in Around the World in Eighty Days (1872).

The earliest modern plantations originated in Jamaica and the related Western Caribbean Zone, including most of Central America. It involved the combination of modern transportation networks of steamships and railroads with the development of refrigeration that allowed bananas to have more time between harvesting and ripening. North America shippers like Lorenzo Dow Baker and Andrew Preston, the founders of the Boston Fruit Company started this process in the 1870s, but railroad builders like Minor C Keith also participated, eventually culminating in the multi-national giant corporations like today's Chiquita Brands International and Dole. These companies were monopolistic, vertically integrated (meaning they controlled growing, processing, shipping and marketing) and usually used political manipulation to build enclave economies (economies that were internally self sufficient, virtually tax exempt, and export oriented that contribute very little to the host economy). Their political maneuvers, which gave rise to the term Banana republic for states like Honduras and Guatemala, included working with local elites and their rivalries to influence politics or playing the international interests of the United States, especially during the Cold War, to keep the political climate favorable to their interests.

The vast majority of the world's bananas today are cultivated for family consumption or for sale on local markets. India is the world leader in this sort of production, but many other Asian and African countries where climate and soil conditions allow cultivation also host large populations of banana growers who sell at least some of their crop.

There are peasant sector banana growers who produce for the world market in the Caribbean, however. The Windward Islands are notable for the growing, largely of Cavendish bananas, for an international market, generally in Europe but also in North America. In the Caribbean, and especially in Dominica where this sort of cultivation is widespread, holdings are in the 1–2 acre range. In many cases the farmer earns additional money from other crops, from engaging in labor outside the farm, and from a share of the earnings of relatives living overseas. This style of cultivation often was popular in the islands as bananas required little labor input and brought welcome extra income. Vulnerability to hurricanes in the northern hemisphere and cyclones in the south destroy crops. After the signing of the NAFTA agreements in the 1990s, however, the tide turned against peasant producers. Their costs of production were relatively high and the ending of favorable tariff and other supports, especially in the European Economic Community, made it difficult for peasant producers to compete with the bananas grown on large plantations by the well capitalized firms like Chiquita and Dole. Not only did the large companies have access to cheap labor in the areas they worked, but they were better able to afford modern agronomic advances such as fertilization. The "dollar banana" produced by these concerns made the profit margins for peasant bananas unsustainable.

Caribbean countries have sought to redress this problem by providing government supported agronomic services and helping to organize producers' cooperatives. They have also been supporters of the Fair Trade movement which seeks to balance the inequities in the world trade in commodities.

Export bananas are picked green, and ripen in special rooms upon arrival in the destination country. These rooms are air-tight and filled with ethylene gas to induce ripening. The vivid yellow color normally associated with supermarket bananas is in fact a side effect of the artificial ripening process. Flavor and texture are also affected by ripening temperature. Bananas are refrigerated to between 56 and 59 °F during transport. At lower temperatures, ripening permanently stalls, and turns the bananas gray as cell walls break down. The skin of ripe bananas quickly blackens in the 39 °F environment of a domestic refrigerator, although the fruit inside remains unaffected.

"Tree-ripened" Cavendish bananas have a greenish-yellow appearance which changes to a brownish-yellow as they ripen further. Although both flavor and texture of tree-ripened bananas is generally regarded as superior to any type of green-picked fruit, this reduces shelf life to only 7–10 days.

Bananas can be ordered by the retailer "ungassed", and may show up at the supermarket fully green. "Guineo Verde", or green bananas that have not been gassed will never fully ripen before becoming rotten. Instead of fresh eating, these bananas are best suited to cooking, as seen in Mexican culinary dishes.

A 2008 study reported that ripe bananas fluoresce when exposed to ultraviolet light. This property is attributed to the degradation of chlorophyll leading to the accumulation of a fluorescent product in the skin of the fruit. The chlorophyll breakdown product is stabilized by a propionate ester group. Banana-plant leaves also fluoresce in the same way. Green bananas do not fluoresce. The study suggested that this allows animals which can see light in the ultraviolet spectrum (tetrachromats and pentachromats) to more easily detect ripened bananas.

Bananas are a staple starch for many tropical populations. Depending upon cultivar and ripeness, the flesh can vary in taste from starchy to sweet, and texture from firm to mushy. Both skin and inner part can be eaten raw or cooked. Bananas' flavor is due, amongst other chemicals, to isoamyl acetate which is one of the main constituents of banana oil.

During the ripening process, bananas produce a plant hormone called ethylene, which indirectly affects the flavor. Among other things, ethylene stimulates the formation of amylase, an enzyme that breaks down starch into sugar, influencing the taste of bananas. The greener, less ripe bananas contain higher levels of starch and, consequently, have a "starchier" taste. On the other hand, yellow bananas taste sweeter due to higher sugar concentrations. Furthermore, ethylene signals the production of pectinase, an enzyme which breaks down the pectin between the cells of the banana, causing the banana to soften as it ripens.

Bananas are eaten deep fried, baked in their skin in a split bamboo, or steamed in glutinous rice wrapped in a banana leaf. Bananas can be made into jam. Banana pancakes are popular amongst backpackers and other travelers in South Asia and Southeast Asia. This has elicited the expression Banana Pancake Trail for those places in Asia that cater to this group of travelers. Banana chips are a snack produced from sliced dehydrated or fried banana or plantain, which have a dark brown color and an intense banana taste. Dried bananas are also ground to make banana flour. Extracting juice is difficult, because when a banana is compressed, it simply turns to pulp. Bananas feature prominently in Philippine cuisine, being part of traditional dishes and desserts like maruya, turrón, and halo-halo. Most of these dishes use the Saba or Cardaba banana cultivar. Pisang goreng, bananas fried with batter similar to the Filipino maruya, is a popular dessert in Malaysia, Singapore, and Indonesia. A similar dish is known in the United States as banana fritters.

Plantains are used in various stews and curries or cooked, baked or mashed in much the same way as potatoes.

Seeded bananas (Musa balbisiana), one of the forerunners of the common domesticated banana, are sold in markets in Indonesia.

Bananas are an excellent source of vitamin B6 and contain moderate amounts of vitamin C, manganese and potassium.

Along with other fruits and vegetables, consumption of bananas may be associated with a reduced risk of colorectal cancer and in women, breast cancer and renal cell carcinoma.

Banana ingestion may affect dopamine production in people deficient in the amino acid tyrosine, a dopamine precursor present in bananas.

In India, juice is extracted from the corm and used as a home remedy for jaundice, sometimes with the addition of honey, and for kidney stones.

Individuals with a latex allergy may experience a reaction to bananas.

A banana tree on Banana Island in Luxor, Egypt.