The onion has been used as an ingredient in various dishes for thousands of years by many cultures around the world. Its world production is steadily increasing so that it is now the second most important horticultural crop after tomatoes.

It belongs to the lily family, the same family as garlic, leeks, chives, scallions and shallots. There are over 600 species of Allium, distributed all over Europe, North America, Northern Africa and Asia.

Onion and other Allium vegetables are characterized by their rich content of thiosulfinates, sulfides, sulfoxides, and other odoriferous sulfur compounds. The cysteine sulfoxides are primarily responsible for the onion flavor and produce the eye-irritating compounds that induce lacrimation. The thiosulfinates exhibit antimicrobial properties.

It is effective against many bacteria including Bacillus subtilis, Salmonella, and E. coli. It is not as potent as garlic since the sulfur compounds present in it are only about one-quarter the level found in garlic.

BOTANICAL NAME – Alluim cepa

FAMILY NAME – Liliaceae


The bulbous root of this plant consists of layers of fleshy scales covered by white, yellow or violet colored tunics. The erect stem is hollow with a swelling at the lower end and can grow as high as 40 inches (1 meter). The hollow leaves, which are almost cylindrical or slightly flattened, have a glabrous surface. The flowers, which have white or purple petals, are clustered into rounded heads. The fruit consists of one capsule and 3 loculi with flat, black seeds.


There are many different varieties - red, yellow, white, and green, each with their own unique flavor, from very strong to mildly sweet. can be eaten raw, cooked, fried, dried or roasted. They are commonly used to flavor dips, salads, soups, spreads, stir-fry and other dishes.


It was native of Persia. Originating in northern Asia and Palestine, it has been cultivated for over 5000 years. It was popular food of Egypt (depicted on tombs in 1500 B.C.). A city was named Onion by Jews that existed for 343 years. It is frequently grown throughout Europe, Egypt, America, India, China, Japan, Malaysia etc. for the edible root (onions). It is gathered from mid-summer onwards depending on the time of planting.

Onion was reputed as a cure and therapy for colds, earaches, warts and poor complexion. It was also believed to be an aphrodisiac and defense against evil. It is featured in northern and eastern European countries.


From January to December


From December to May


Bulb and twigs


• Stimulant

• Diuretic

• Expectorant

• Aphrodisiac

• Emmenaagogue

• Anti-flatulent

• Anti-dysenteric

• Cardio tonic

• Bactericidal

• Reduces blood sugar

• Lowers cholesterol

• Anti-inflammatory

• Hypo-tensive

• Anthelmintic

• Anti-sclerotic

• Analgesic

• Anti-neuralgic

• Anti-rheumatic

• Corn remover


Nutritive value of onion has been discussed here.

Its analysis gives the following composition per 100 gm of edible part:

• Moisture – 86.6%

• Protein – 1.2%

• Fat – 0.1%

• Fiber – 0.6%

• Carbohydrates – 11%

• Minerals – 0.4%

• Calcium – 48 mg

• Phosphorus – 50 mg

• Iron – 0.7 mg

• Vitamin C – 11 mg

• Small amount of vitamin B-complex

• Caloric value – 51


They can be peeled and cut into a required style like rings and quarters or chopped. It may be eaten raw, dried, fresh, cooked, or as a seasoning.


It should be stored in a cool, dry and dark place.

Read about the Benefits of Onion in the next article....

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