The shallot is a plant belonging to the same family as garlic and onion. The term refers to both the plant and the bulb it produces, used as a condiment and as a vegetable. This bulb is made up of many layers of leaves, wrapped on one another, but often forming several bulbils. It is protected by a coppery, dry and shiny skin (tunic).
History of shallot
It has long been believed, under the botanical name Allium ascalonicum, the shallot was a species in itself. However, thanks to molecular analysis, it is now known that it’s a subspecies of onion (A. cepa var. aggregatum), especially since the two plants cross without difficulty, a sign of close kinship. But which does not prevent them from being very different from each other. Exception to this rule is the grey shallot, the favorite of the gourmets, which is attached to the species Allium oschaninii, and whose wild species is still found in the Middle East.
The shallot would come, as its cousin the Onion, from Southwest Asia, the Mediterranean basin and the Middle East. Under the selection pressure, researchers would have obtained, from the onion, very different varieties from what they knew so far. This transformation would have occurred at the turn of our era, even before, because the shallot was already used in Persia and Assyria at that time. In France, it is found under Charlemagne (circa 600 A.D.). It will reach America from the moment of colonization: it is particularly appreciated in Louisiana, where the Cajuns always give it a great place in their kitchen.
The term “shallot” is commonly used incorrectly to designate the green onion. The shallot is rather a small vegetable of the size of a bulb of garlic, with a more subtle flavor than the onion. There are several varieties, the three most common being the grey shallots, jersey and “chicken thigh”.
Active principles and properties
Several prospective and epidemiological studies revealed that high consumption of fruits and vegetables reduced the risk of cardiovascular disease, certain cancers and other chronic diseases. In addition, foods from the alliums family (including shallots, onions, green onions, garlic, chives and leeks) are recognized for their protective effects against some cancers.
Antioxidants. Antioxidants are compounds that protect the body’s cells from damage caused by free radicals. The latter are highly reactive molecules that would be involved in the development of cardiovascular diseases, certain cancers and other diseases related to aging. According to the results of an in vitro study, shallot extracts show an antioxidant activity similar to that of garlic extracts. In other studies, the antioxidant activity of shallots has been found to be greater than that of different varieties of onions and cabbages. This strong antioxidant activity would be attributable to flavonoids contained in shallots. The shallot is fourth in terms of its flavonoid content, among ten varieties of onions. It should be noted that onions are an important source of flavonoids, particularly in the form of quercetin, in the food.
The shallot also contains significant amounts of beta-carotene, a compound of the carotenoid family. The latter have antioxydantes properties. As a comparison, 125 ml (1/2 cup) of shallot contains about 600 ug of beta-carotene, while red pepper and cantaloupe, known for their high beta-carotene content, contain two and three times as much respectively.
Sulfur compounds. The shallot would contain some sulfur compounds, less well known than those present in other alliums, such as garlic for example. The protective effect of alliums against certain cancers, mainly those of the digestive system, appears to be related to their content in sulfur compounds. Moreover, it is these substances which give them their taste so caracteristic. To date, the effects of the sulfur compounds of the shallot have not been specifically evaluated.
Antimicrobial effect. Shallot extracts, as well as extracts of garlic and onion, showed an antimicrobial effect in vitro against fungi and bacteries. In the shallot, researchers isolated a specific peptide that would be partly responsible for its antifungal action. Other shallot proteins or peptides may also contribute to this effect, but this remains to be verified. In addition, human studies must be conducted before concluding an antimicrobial effect related to the consumption of shallots.
Quercetin and lactose intolerance
In lactose-intolerant individuals, the activity of lactase is diminished and sometimes absent. Lactase is the enzyme that allows the digestion of lactose present in milk and in some dairy products. This enzyme could also play a role in the digestion and absorption of quercetin, a flavonoid found in the vegetables of the alliaceous family. An in vitro study showed that lactase could improve the uptake of quercetin from food, including shallot and onions. However, studies among humans should be carried out to accurately assess the absorption of this flavonoid in lactose-intolerant people.
Choice and conservation
Buy very firm and germ-free bulbs.
To peel, first cut the shallot in half lengthwise. The operation will be less painful for the eyes, especially with regard to the grey.
The grey shallot is preserved only a few weeks after its harvest in the fall. Hence the difficulty of finding it out of season. The other varieties keep a few months.
Keep all types of shallots dry and at room temperature, in a paper bag or mesh bag. Avoid the refrigerator and hot spots, especially in the vicinity of the stove.
The grey shallot is planted in the fall at the same time as garlic, 10 cm or 15 cm spacing. Protect it from cold and temperature changes by applying good mulch after planting. Remove the mulch in the spring to allow the soil to thaw, then put it back a few weeks later to prevent the emergence of weeds. Like all alliums, shallots are a poor competitor against weeds. The other types of shallots plant early in the spring, as soon as it is possible to go to the garden.
Choosing, for planting, medium or large bulbs rather than small ones, the nutrient reserves of the latter being insufficient to ensure good growth and therefore a good harvest. Do not plant a sick or desiccated bulb. Since the roots are superficial, it is important to irrigate regularly. However, you should stop watering two or three weeks before the harvest.
Although shallots require a good supply of nitrogen, avoid late spreading at the risk of compromising the quality of the bulb during storage. The first green stalks may be harvested one or two months after planting or lifting. Depending on the varieties, the bulbs will be 90 to 120 days to ripen. After harvesting, dry the bulb with its fanes in an airy place. The leaf stalks will only be removed when the bulb is perfectly dry.