The shallot is a botanical variety of the species Allium cepa, to which the multiplier onion also belongs. The shallot was formerly classified as a separate species, A. ascalonicum, a name now considered a synonym of the currently accepted name. The genus Allium, which includes onions and garlic as well as shallots, is now classified in the plant family Amaryllidaceae, but was formerly considered to belong to the separate family Alliaceae.
Like garlic, shallots are formed in clusters of offsets with a head composed of multiple cloves. The skin colour of shallots can vary from golden brown to gray to rose red, and their off-white flesh is usually tinged with green or magenta.
Shallots are extensively cultivated for culinary uses, propagated by offsets. In some regions ("long-season areas"), the offsets are usually planted in autumn. In some other regions, the suggested planting time for the principal crop is early spring.
In planting, the tops of the bulbs should be kept a little above ground, and the soil surrounding the bulbs is often drawn away when the roots have taken hold. They come to maturity in summer, although fresh shallots can now be found year-round in supermarkets. Shallots should not be planted on ground recently manured.
In Africa, shallots are grown in the area around Anloga in southeastern Ghana.
Shallots have better nutrition profile than onions. On weight per weight basis, they have more anti-oxidants, minerals, and vitamins than onions.
They are rich source of flavonoid anti-oxidants such as quercetin, kemferfol…etc. Further; they contain sulphur anti-oxidant compounds such as diallyl disulfide, diallyl trisulfide and allyl propyl disulfide. These compounds convert to allicin through enzymatic action following disruption of their cell surface while crushing, and chopping.
Research studies show that allicin reduces cholesterol production by inhibiting the HMG-CoA reductase enzyme in the liver cells. Further, it also found to have anti-bacterial, anti-viral, and anti-fungal activities.
Allicin also decreases blood vessel stiffness by releasing vasodilator chemical nitric oxide (NO) and thereby help bring a reduction in the total blood pressure. Further research studies suggest that allicin inhibit the platelet clot-formation in the blood vessels that helps decrease an overall risk of coronary artery disease (CAD), peripheral vascular diseases, and stroke.
The phyto-chemical compounds allium and Allyl disulfide in onion have anti-mutagenic (protects from cancers) and anti-diabetic properties (helps lower blood sugar levels in diabetics).
Shallots contain several fold more concentration of vitamins and minerals than in onions, especially vitamin A, pyridoxine, folates, thiamin, vitamin C etc. Pyridoxine (B-6) helps raises GABA chemical levels in the brain that help sooth nervous irritability. In addition, 100 g fresh shallots have 1190 IU of vitamin A. Vitamin A is a powerful antioxidant that helps protect from lung and oral cavity cancers.Further, they are also good in minerals and electrolytes than onions; particularly iron, calcium, copper, potassium, and phosphorus.
Read More at Wikipedia