Momordica charantia

Description

This herbaceous, tendril-bearing vine grows up to 5 m (16 ft) in length. It bears simple, alternate leaves 4–12 cm (1.6–4.7 in) across, with three to seven deeply separated lobes. Each plant bears separate yellow male and female flowers. In the Northern Hemisphere, flowering occurs during June to July and fruiting during September to November.

The fruit has a distinct warty exterior and an oblong shape. It is hollow in cross-section, with a relatively thin layer of flesh surrounding a central seed cavity filled with large, flat seeds and pith. The fruit is most often eaten green, or as it is beginning to turn yellow. At this stage, the fruit's flesh is crunchy and watery in texture, similar to cucumber, chayote or green bell pepper, but bitter. The skin is tender and edible. Seeds and pith appear white in unripe fruits; they are not intensely bitter and can be removed before cooking.

As the fruit grows, the flesh (rind) becomes somewhat tougher and more bitter, and many consider it too distasteful to eat. On the other hand, the pith becomes sweet and intensely red; it can be eaten uncooked in this state, and is a popular ingredient in some Southeast Asian salads.

When the fruit is fully ripe, it turns orange and mushy, and splits into segments which curl back dramatically to expose seeds covered in bright red pulp.

Varieties

Bitter melon comes in a variety of shapes and sizes. The cultivar common in China is 20–30 cm (7.9–11.8 in) long, oblong with bluntly tapering ends and pale green in color, with a gently undulating, warty surface. The bitter melon more typical of India has a narrower shape with pointed ends, and a surface covered with jagged, triangular "teeth" and ridges. It is green to white in color. Between these two extremes are any number of intermediate forms. Some bear miniature fruit of only 6–10 cm (2.4–3.9 in) in length, which may be served individually as stuffed vegetables. These miniature fruit are popular in Bangladesh, India (common name 'Karela'), Pakistan, Nepal and other countries in South Asia. The sub-continent variety is most popular in Bangladesh and India.

Culinary uses

Bitter melon is generally consumed cooked in the green or early yellowing stage. The young shoots and leaves of the bitter melon may also be eaten as greens.

In Chinese cuisine, bitter melon (Chinese: 苦瓜, pinyin: kǔguā or kugua) is valued for its bitter flavor, typically in stir-fries (often with pork and douchi), soups, dim sum, and herbal teas (See Gohyah tea). It has also been used in place of hops as the bittering ingredient in some beers in China and Okinawa.

Bitter melon is very popular throughout India. In North Indian cuisine, it is often served with yogurt on the side to offset the bitterness, used in curry such as sabzi or stuffed with spices and then cooked in oil.

In South Indian cuisine, it is used in the dishes thoran/thuvaran (mixed with grated coconut), mezhukkupuratti (stir fried with spices), theeyal (cooked with roasted coconut) and pachadi (which is considered a medicinal food for diabetics). Other popular recipes include preparations with curry, deep fried with peanuts or other ground nuts, and Pachi Pulusu, a soup with fried onions and other spices. In Tamil Nadu, where it is known as paagarkaai or pavakai (பாகற்காய்) in Tamil, a special preparation called pagarkai pitla, a kind of sour koottu, variety is very popular. Also popular is kattu pagarkkai, a curry that involves stuffing with onions, cooked lentil and grated coconut mix, tied with thread and fried in oil. In the Konkan region of Maharashtra, salt is added to finely chopped bitter gourd, known as karle (कारले) in Marathi, and then it is squeezed, removing its bitter juice to some extent. After frying this with different spices, the less bitter and crispy preparation is served with grated coconut. In Kannada it is known as haagalakaayi.

In northern India and Nepal, bitter melon, known as tite karela (तीते करेला) in Nepali, is prepared as a fresh pickle. For this, the vegetable is cut into cubes or slices, and sautéed with oil and a sprinkle of water. When it is softened and reduced, it is crushed in a mortar with a few cloves of garlic, salt and a red or green pepper. It is also eaten sautéed to golden-brown, stuffed, or as a curry on its own or with potatoes.

In Sri Lanka it is known as karavila (කරවිල) in Sinhala, and is an ingredient in many different curry dishes (e.g., Karawila Curry and Karawila Sambol) which are served mainly with rice in a main meal. Sometimes large grated coconut pieces are added, which is more common in rural areas. Karawila juice is also sometimes served there.

In Pakistan, known as karela (کریلا) in Urdu-speaking areas, and Bangladesh, known as korola (করলা|করলা) in Bengali, bitter melon is often cooked with onions, red chili powder, turmeric powder, salt, coriander powder, and a pinch of cumin seeds. Another dish in Pakistan calls for whole, unpeeled bitter melon to be boiled and then stuffed with cooked minced beef, served with either hot tandoori bread, naan, chappati, or with khichri (a mixture of lentils and rice).

Bitter melon, known as gōyā (ごーやー) in Okinawan, and nigauri (苦瓜) in Japanese (although the Okinawan word gōyā is also used), is a significant ingredient in Okinawan cuisine, and is increasingly used in Japanese cuisine beyond that island. It is popularly credited with Okinawan life expectancies being higher than the already long Japanese ones.

In Indonesian cuisine, bitter melon, known as pare in Javanese and Indonesian, is prepared in various dishes, such as gado-gado, and also stir fried, cooked in coconut milk, or steamed.

In Vietnamese cuisine, raw bitter melon slices known as mướp đắng or khổ qua in Vietnamese, eaten with dried meat floss and bitter melon soup with shrimp are popular dishes. Bitter melons stuffed with ground pork are served as a popular summer soup in the south. It is also used as the main ingredient of "stewed bitter melon". This dish is usually cooked for the Tết holiday, where its "bitter" name is taken as a reminder of the bitter living conditions experienced in the past.

In Thai cuisine, the Chinese variety of green bitter melon, mara (มะระ) in Thai, is prepared stuffed with minced pork and garlic, in a clear broth. It is also served sliced, stir fried with garlic and fish sauce until just tender.

In the cuisine of the Philippines, bitter melon, known as ampalaya in Tagalog, and parya in Ilokano, may be stir-fried with ground beef and oyster sauce, or with eggs and diced tomato. The dish pinakbet, popular in the Ilocos region of Luzon, consists mainly of bitter melons, eggplant, okra, string beans, tomatoes, lima beans, and other various regional vegetables all stewed together with a little bagoong-based stock.

In Trinidad and Tobago bitter melons, known as caraille or carilley, are usually sautéed with onion, garlic and scotch bonnet pepper until almost crisp.

In Mauritius bitter melons are known as 'margose' or 'margoze'.

Traditional medicinal uses

They are in use since a very long time in Hindu medicine or Ayurveda. Bitter melon has been used in various Asian and African herbal medicine systems for a long time. In Turkey, it has been used as a folk remedy for a variety of ailments, particularly stomach complaints. In traditional medicine of India different parts of the plant are used as claimed treatments for diabetes (particularly Polypeptide-p, an insulin analogue),and as a stomachic, laxative, antibilious, emetic, anthelmintic agent, for the treatment of cough, respiratory diseases, skin diseases, wounds, ulcer, gout, and rheumatism.

Momordica charantia has a number of purported uses including cancer prevention, treatment of diabetes, fever, HIV and AIDS, and infections. While it has shown some potential clinical activity in laboratory experiments, "further studies are required to recommend its use".

For fever reduction and relief of menstrual problems, there is no scientific research to back these claims. For cancer prevention, HIV and AIDS, and treatment of infections, there is preliminary laboratory research, but no clinical studies in humans showing a benefit.

With regard to the use of Momordica charantia for diabetes, several animal studies and small-scale human studies have demonstrated a hypoglycemic effect of concentrated bitter melon extracts. In addition, a 2014 review shows evidence that Momordica charantia, when consumed in raw or juice form, can be efficacious in lowering blood glucose levels. However, multiple reviews have found that Momordica charantia does not significantly decrease fasting blood glucose levels or A1c, indicators of blood glucose control, when taken in capsule or tablet form. Momordica charantia may be beneficial in diabetes, however the effects seem to depend on how it is consumed. More studies need to be performed in order to verify this effect. The Memorial Sloan Kettering Cancer Center concludes that bitter melon "cannot be recommended as a replacement therapy for insulin or hypoglycemic drugs".

Adverse effects

Reported side effects include diarrhea, abdominal pain, fever, hypoglycemia, urinary incontinence, and chest pain. Symptoms are generally mild, do not require treatment, and resolve with rest.

Pregnancy

Bitter melon is contraindicated in pregnant women because it can induce bleeding, contractions, and miscarriage.