Manna

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Manna
Manna, general name for several food substances, mostly sweetening agents, derived from unrelated plants. Flowering, or manna, ash, Fraxinus ornus, produces from incisions an exudate that is 80 percent mannitol, a sugar alcohol, and is grown for this purpose in Sicily. Some members of the legume family, Alhagi species, native to Egypt and Syria, produce a similar kind of manna as an exudate on twigs. When it solidifies the bushes are shaken, knocking off the manna. When the scale insect Coccus manniparus punctures the bark of a Mediterranean species of tamarisk, Tamarix mannifera, a sweet substance is produced that falls to the ground and solidifies. Some experts believe that the manna of the Bible was the lichen Lecanora esculenta, or a related species. Arabs still gather this lichen and mix it with meal to produce bread. When dry, it can be torn from the soil and transported by the wind, producing a “rain” of food.

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