Fruit of the angels.
- Christopher Columbus
The papaya, Carica papaya, is a member of the family Caricaceae. In Australia and the West Indies, it is known as papaw, or pawpaw1. To make matters worse, words like papaya and tortilla are slang for male and female genitalia in some Spanish-speaking countries.
The fruit also has many other names worldwide: Kapaya, kepaya, lapaya or tapaya in parts of Asia. In French, it is papaya, or sometimes figue des Iles. In Spanish it is often called melón zapote, lechosa, payaya, fruta bomba, mamón or papayo. In Brazil, the usual name is mamao. When European explorers first encountered papaya in the New World, they called it a tree melon.
The papaya plant is not a tree but a large herb reaching 20 to 30 feet and its 'trunk' is technically a hollow stem. The green, waxy leaves grow from the stem and have about seven wide 'fingers' with yellow ribs and veins. The stem and leaves contain a milky latex sap.
Some papaya plants are male and others are female, so it takes cross-pollination for fruit to be produced. Very rarely, a plant may be hermaphrodite and pollinate itself. Even more rarely, a plant can cross genders (usually in the hot season) or even completely and permanently transform from a male to a female plant (most often after being pruned at the top).
Papaya flowers have five petals, and are whitish, waxy and slightly fragrant. The male flower is usually between one and two inches wide while the female is slightly larger.
The cultivated papaya fruit looks a bit like an elongated melon 6 - 20 inches long; wild plants have tiny fruits. The peel is thin and waxy but tough, and the green, unripe fruit is rich in latex. As it ripens, the fruit skin turns yellow and the flesh softens, turns a deep orange salmon colour and gives off a fantastic sweet aroma. Ripe papaya is juicy, sweet and tastes a bit like a cantaloupe. The seeds are black and shiny like caviar and sit in a fibrous, gelatinous mess in the ridged cavity at the centre of the fruit.
An Equatorial Being
The papaya is believed to be native to tropical America but is now grown all along the equator. There are many different varieties of papaya as it has been in active cultivation for a couple of centuries and has spread to all the countries that have the right environment for it, including South and Latin America, Mexico, Southern US states, Australia, sub-Saharan Africa, Hawaii, India and the Far East.
Fruits are hand-harvested carefully to avoid scratching the skin, which would release latex and stain the skin. Below 50°F [10°C], papayas experience chilling injury. Papayas are extremely perishable; shelf life at room temperature ranges from three to eight days.
- Mark Rieger, Professor of Horticulture at the University of Georgia, USA.
The papaya needs a tropical climate that is dry when cold and wet when warm, hence its greatest success in the equatorial zone with its warm wet season and cool dry season2. It is extremely sensitive to frost and water-logging will kill the taproot within 48 hours. The papaya is especially susceptible to parasites, pests and diseases. This fussy plant needs a lot of water but must have good drainage and it bears most fruit in light, porous, slightly acidic soils that are rich in organic matter. Papaya is usually grown from seed but it can also be grown from cuttings.
Half of a papaya has 30 calories. A papaya is an excellent source of Vitamin C, and is also rich in vitamins A and B.
- United States Department of Agriculture
The Ripe Papaya
Ripe papaya fruit is usually eaten fresh. Cut the fruit in half lengthways, scoop out and discard the seeds, and serve with a wedge of lemon or lime. The flesh can be scooped into balls and served in a fruit salad. This fruit can also be used in a coulis3 or as an ice cream flavouring, cooked in a pie, pickled, made into jam, crystallised, juiced or frozen. A ripe but still firm papaya can be baked then served with honey and lemon. Unfortunately, papaya cannot be used to make jelly as the papain (see below) prevents the gelatine from firming.
The Green Papaya
Unripe or green papaya is inedible when raw and must be peeled and boiled before being pickled, added to a salad or served as a vegetable. It is also often stewed in a soup.
Leaf, Flower and Stem
Papaya leaves contain potent alkaloids which can stimulate the heart and lungs with a similar action to digitalis, but these are destroyed in cooking. Tender, young leaves are boiled like spinach in the East Indies. The male flowers are boiled for a savoury meal in Asia, while in Indonesia they are often boiled and candied for a dessert. In some African cultures, the tender young stems are cooked much like asparagus while the older, tougher stem is peeled then grated, pounded, strained and the resultant 'mash' is boiled.
Papain in Industry
The latex of the papaya plant and its green fruits contains two proteolytic4 enzymes: papain5 and chymopapain. The latter is most abundant but papain is twice as potent.
Papain breaks down meat and is best known as a commercially-prepared tenderising cooking ingredient. It is important to thoroughly cook treated meat to inactivate the enzyme, which is heat resistant. If treated meat is stored after cooking (say, as a leftover or because it was cooked a long time before serving) the tenderising action may continue and the meat will digest to an unpleasant texture.
Papain has many other industrial talents. It is used to clarify beer, treat wool and silk before dyeing, and to depilate hides before tanning. It is also often spread on tuna liver before oil extraction, making the oil richer in vitamins A and D. Papain can be found in toothpaste6, chewing gum, detergents, shampoos, cosmetics and creams among other things.
The Healing Papaya
Studies at the University of Nigeria have revealed that extracts of ripe and unripe papaya fruits and the seeds are active against gram-positive bacteria. Strong doses are effective against gram-negative bacteria7.
- Fruits of Warm Climates by J Morton
Papain is used in pharmaceutical digestive aids and there are ongoing studies on its effect on cancer-causing cells and the Herpes simplex virus. The other papayan enzyme, chymopapain, has been used in the treatment of slipped spinal discs8 or pinched nerves.
As a last resort in a London hospital in 1977, a post-operative infection in a kidney-transplant patient was cured by laying strips of papaya on the wound for two days.
- Fruits of Warm Climates
Chris Rudge, Medical Director of NHS UK Transplant talked recently on Radio 4 about his use of papaya in transplant surgery.
Packages of dried, pulverised leaves are sold for making tea, despite the fact that the leaf decoction is administered as a purgative for horses in Ghana and in the Ivory Coast it is a treatment for genito-urinary ailments.
- National Tropical Botanical Garden, Hawaii, USA
Papain has been used to treat ulcers, diphtheria, and impaction in the throat. People who have insufficient saliva are given semi-dried papaya fruit to chew on before eating to help them digest their food better. The dried leaves have even been smoked to relieve asthma or as a tobacco substitute. In Traditional Chinese Medicine papaya is used to expel wind-dampness, relax tendons, regulate the stomach and promote digestion.
Papaya is oestrogenic (it has compounds that act as the female hormone oestrogen). It is used in folk medicine to promote milk production, facilitate childbirth and increase the female libido. In some parts of the world, it is used to bring forward menstruation, and sometimes even to induce an abortion.
Papaya's action on protein has traditionally been useful in herbal treatment of conditions such as leprosy, psoriasis, fungal and bacterial skin infections and even dandruff. It is reputed to help prevent skin disorders such as boils, warts and freckles by topical application of the fresh latex and is used to treat stings, sores and boils as well as being prescribed as a vermifuge9.
Other Uses for Papaya
The papaya 'flower essence' is supposed to increase memory retention and assimilation of data obtained on higher planes as well as ease emotional tension and sexual identity crises.
The papaya has long been used in magical rites. Apparently, if you tie a rag around a limb of a papaya tree while visualising your need, your wish will be fulfilled. On the other hand, it is said that hanging papaya twigs over the doorsill will keep evil from entering the house and that if you eat the fruit and simultaneously serve it to the object of your desires, feelings of love will intensify.
Papaya in all its forms is extremely dangerous for people with a latex allergy10 (causing anaphylactic shock), and it has been suggested that too much papaya might induce prostate cancer.