Asparagus is a plant in the Asparagaceae family native to the eastern Mediterranean. Known to the Romans, it has been cultivated as a vegetable in France since the 15th century. The term also designates its edible shoots, which come from rhizomes from which leave each year the underground buds or shoots which give rise to stems rising between 1 and 1.5 meters.
Description
Asparagus is a perennial plant thanks to its claw; its development is particular. The claw is formed from a seed, it is composed of a rhizome which has eyes (buds) at the top and fleshy roots radiating in a star at the bottom. From year to year, it is the claw which ensures on the one hand the survival of the plant and on the other hand the future harvest. Each year, at the end of the harvest, a new claw forms during the summer period; it grows thanks to its own new roots. Green stems, branched and provided with cladodes produce, thanks to photosynthesis, carbon elements which accumulate in the fall in large roots. It is these reserves which will be used in the following spring for the growth of spears that grow in a mound of earth when no aerial green part exists. The spears (consumed part of the asparagus) form straight stems up to 1.5 meters high with fine, branched foliage. Asparagus, including edible asparagus, do not have functional leaves. These are the cladodes which grow in bouquets on the stems which play the role of leaves. The true leaves are reduced to tiny translucent scales.
It is an allogamous and dioecious species. Male feet first produce edible shoots which later produce flowers with pollen-emitting stamens, while shoots that develop on female feet form flowers which, when fertilized by pollen , produce small red berries, fruit, containing several black seeds. The metabolic cost to produce these seeds exhausts the female feet, so we rather use the male plants in the asparagus.
Medicinal propertiesFrom the same family as garlic and onion, asparagus has common components with these two plants: richness in vitamins A, B9 and PP, phosphorus and manganese. It also contains asparagine and asparagusic acid. This substance - as well as S-methylmethionine - is transformed during digestion into odorous sulfur products including methanethiol (or methyl-mercaptan). Within 15 minutes of consumption, the urine may then have a very characteristic odor.
According to several studies, part of the population does not metabolize these two precursors into odorous compounds, another part is devoid of the olfactory endings allowing it to detect them. This explains why some people do not perceive this particular odor. Note that the proportion of people with a metabolism of odorous sulfur compounds can be very variable from one population to another. While two publications give a proportion between 40 and 45% for the British population, another gives 100% (out of 103 people) in France.
Origin
This species is native to temperate regions of Eurasia: central and southern Europe, North Africa, central and western Asia. It grows in sandy terrain in the wild. It has been cultivated since Antiquity, but the development of varieties dates from the 18th century. The Greek Geoponics indicate that the asparagus is the fruit of buried ram's horns. This belief persisted until the middle of the 17th century3.
From 1805, it made the reputation of Argenteuil, where it was no longer cultivated. It is now widely cultivated in many countries on all continents, although the world's leading exporter of canned asparagus is China. Chile and Peru remain important producers.
In the wild there are twelve species in Europe, including five in France according to Tela Botanica [archive]: Asparagus officinalis, Asparagus acutifolius very common in the south, Asparagus macrorrhizus, Asparagus albus and Asparagus tenuifolius. All are edible, but the asparagus is very bitter.