Growing upon nonwoody stems, banana fruits come from tropical plants that are not trees but one of the world's largest herbs. Fertile, moist and warm soils cause fast growth and production of flowers that develop into fruits without pollination. After a stem produces fruits, it degrades and dies but not before the roots sprout up replacement "pup" plants to grow and fruit in the future.
The tropical reaches of Indo-Malaysia to northernmost Australia is considered the origin of banana plants. According to Purdue University and "Economic Botany: Plants in Our World," bananas were grown in India by 600 B.C. By 900 A.D. they were first carried into Europe, where previously they were only heard of in stories. Arabs may have helped introduce bananas into equatorial Africa, and by the 1500s bananas made it to America via the slave trade. In the late 19th century United States, the United Fruit Company began massive exportation of bananas via refrigerated steamships and led to massive land holdings across Central America and northern South America dubbed "the banana republics." By World War II, United Fruit's power waned in the region as new political borders and powers developed, but the banana fruit remained as a lasting food staple.
Centuries of hybridization and cultivation of bananas centered around two primary species: Musa acuminata (A) and Musa balbisiana (B). Each species provided a chromosome set and when crossed would produce varieties with AA, AB, BB designations. Manipulations led to bananas having three or four times the usual chromosome numbers and larger-sized fruits, and had designations like AAA, ABB, BBB, etc. Thus, modern edible bananas lack seeds and have complex genetic lineages and botanically are best only represented by the generic Musa name rather than reference to specific species according to "Economic Botany: Plants in Our World."
Banana flowers develop on long, pendulous stalks, from the leaf canopy on banana plants. Female flowers appear at the base of the elongating stalk and the male flowers only at the tip of the stalk. Modern bananas do not require pollination or fertilization of female ovaries for fruit production. The female flowers occur in "hands" or "bunches" with two whorls. As the bananas form, they plump and elongate while they point upwards on the stalk. For harvest, they are cut off when still green and protected so to prevent bruising, which releases carbon dioxide and ethylene that hasten ripening and decay. If the bananas are kept between 56 to 75 degrees Fahrenheit and 85 to 95 percent humidity, ripening is delayed, which allows for easy and timely shipment of fruits according to Purdue University. Once at their final destination, warmth and ethylene gas can ripen fruits to sale quality.
A cup of mashed banana supplies 28 g sugars in 200 calories, according to the Nutrition Data website. As part of daily food values recommended by the U.S. Department of Agriculture, this quantity of banana provides 23 percent of needed daily dietary fiber, 17 percent of daily carbohydrates, 33 percent of vitamin C, 41 percent of vitamin B6, 30 percent of manganese and 23 percent of potassium.
The banana fruit often makes a perfect raw snack, eaten fresh without the peel, but it also can be baked or boiled and added to other meal components. Plantains are bananas with significantly higher starch levels. Purees, alcoholic and nonalcoholic beverages and syrups also can be made of pulverized banana flesh. Dried flesh ground up makes a flour or powder. Peels from bananas help tan leather, make soap or fabric dyes. If burned, they make a spice for use on food, especially in India. Moreover, Purdue University lists several medicinal uses for both banana flesh and peels, including antifungal and antibiotic applications.