Difference Between Onion and Scallion (With Table)

The stems of some plants are modified to serve for storage. The most common modification is in the form of a bulb. It is condensed as a terminal bulb and axial fleshy leaves. Such modified stems of plants are widely used and eaten daily. The two common forms of bulbs are onions and scallions.

Onion vs Scallion

The main difference between onion and scallion is that the onion has a larger bulb while the scallion has a smaller bulb. The taste of onion is sharp and strong while the taste of scallion is milder. They belong to the same genus Allium but are different species.

Onions have a longer growth period. The scientific name of onion is Allium cepa. It produces an irritant called syn-Propanethial-S-oxide and stimulates the lachrymal glands. It converts the sulfoxides amino acid to sulfenic acid and causes tears while chopping onions. Onion has several health benefits like lowering the risk of cancer, heart diseases, stroke, diabetes, Alzheimer’s disease. It is a good source of vitamins and minerals.

On the other hand, scallions have a shorter growth period. The scientific name of the scallion is Allium fistulosum. It does not produce any chemical irritant during chopping. It is rich in fiber, antioxidants, and several vitamins and minerals. It is an excellent source of energy and metabolism production.

Comparison Table Between Onion and Scallion

Parameters of ComparisonOnionScallion
Bulb size Large and fully developed bulb Small and under-developed bulb
Health benefits It contains anti-inflammatory substances that reduces cholesterol and triglycerides and is rich in antioxidants and sulfur It is a good source of Vitamin C, and other B-complex vitamins like B1, B2, and B3 vitamin commonly called thiamine, riboflavin, and niacin respectively, and contains several minerals like calcium, potassium
pH Around 5.5 6.0 – 7. 0
Growth conditionsGrows well in loamy, alluvial soil and can withstand temperature variations except extreme hot, cold or rainfallOrganic and moist soil and grows well in full sun to a partially shaded area
Growth periodLonger than scallions Shorter than onions (60 – 120 days)

What is Onion?

Onion is a vegetable species of the genus Allium. It is also called a common onion or bulb onion. The scientific name of onion is Allium cepa. It was first described by Carl Linnaeus. Onion is from the kingdom of Plantae, order of asparagates, a family of Amaryllidaceae, subfamily of allioideae, and genus of allum.

Onion is a biennial or perennial plant and is cultivated annually. It has been grown for over 7000 years. The harvesting time of onion is the first season of its growth. After harvesting, the crop is dried and stored. The plant consists of a bulb at the base, fibrous roots that extend into the soil, and leaves on the top. The bulb is condensed and compressed stems surrounded by modified scales that are fleshy.

The ph of the onion is 5.5. The first cultivation of onion is considered to be done in Central Asia. And there has been evidence that onions were used back in the Bronze Age settlements. The first person to write about the usage of onion and cabbage is Pliny the Elder, in his work called Pompeii.

The crop is susceptible to pests and worms like onion eelworm, onion fly, and another fungus. Some types of onions also produce multiple bulbs. Such types are potato onions and shallots. Onions can be eaten raw in salads, chutneys, and pickles or be cooked along with other savory dishes.

What is Scallion?

Scallions are perennial vegetables of the genus Allium. Scallion and shallot are related and the words are derived from Ancient Greek. The scallion crop does not have a fully developed bulb and has thick, tubular, and hollow leaves growing over the soil. The germination period of the scallion is one to two weeks.

The leaves as well as the bulb of scallion can be eaten raw in salads, salsas, soup, seafood dishes, noodles, and other dressings or cooked and used in other savory dishes. Regions like the Southwest United States eat scallions with salt, cheese, and lime juice. It is also used as a topping of several cuisines.

Scallions require over one inch of water for over a week during cultivation. The ideal soil type for scallion crops is moist, yet not soggy. Scallion is a good source of Vitamin C, and other B-complex vitamins like B1, B2, and B3 vitamin commonly called thiamine, riboflavin, and niacin respectively. It also contains several minerals like calcium, carotenoids, potassium and is rich in antioxidants.

Scallions have several regional names like green onion, spring onion, salad onion, long onion, table onion, onion stick, wild onion, precious onion, yard onion, baby onion, gibbon, and many other such names. Scallion is adaptable to flash freezing. Oils from scallion are widely used. Scallions are active ingredients in Asian cuisine.

Main Differences Between Onion and Scallion

  1. Onions have a stronger taste and smell while scallions have a milder taste.
  2. Onions have a fully developed bulb while scallions lack a fully developed bulb.
  3. The scientific name of onion is Allium cepa while the scientific name of the scallion is Allium fistulosum.
  4. The germination period of onions is six to twelve days while the germination period of the scallion is one to two weeks.
  5. Onions require the loamy, alluvial, friable, and deep type of soil while scallion require moist organic soil that drains well for cultivation.

Conclusion

Both have the same genus Allium but are of different species. Onion belongs from the species of cepa while scallion belongs from the species of fistulosum. They have close relatives, which are chive, garlic, leek, and shallot. They are forms of modified stems.

Onion and scallion look similar and confusing. The distinct difference between both the vegetables lies in the size of the bulb. Both the vegetables are widely used in various cuisines and can be eaten raw as well as cooked.

They contain several vitamins and minerals and have numerous health benefits. They have been proven to reduce the risk of many diseases. Both vegetables should be consumed regularly with a balanced diet.

References

  1. https://pubs.acs.org/doi/abs/10.1021/jf980344x
  2. https://www.koreascience.or.kr/article/JAKO201207364424215.page
x
2D vs 3D