a secretion of the mandibular and pharyngeal glands discharged by worker nurse-bees in special cells of the honeycomb (queen cells), in which the queen bees develop.
The bees deposit 0.2-0.5 grams of royal jelly in one queen cell. In order to secrete royal jelly, the nurse-bees need, besides honey, pollen or beebread. In dry form royal jelly contains 40-58 percent protein, 5-18 percent fat, about 26 percent sugar, and a number of mineral salts, as well as vitamins and other biologically active substances. The composition of royal jelly depends mainly on the pollen the bees are feeding on. Apilac, a preparation used in medicine and perfume, is made from royal jelly.