Sinapis Alba. U.S. White Mustard. Sinap. Alb. [Yellow Mustard]
Related entry: Sinapis nigra
"The ripe seeds of Sinapis alba, Linné (Fam. Cruciferae), without the presence or admixture of more than 5 per cent. of other seeds or other foreign matter. Preserve powdered White Mustard in tightly-closed containers." U. S.
Sinapis Albae Semina, Br. 1898; White Mustard Seeds; Yellow Mustard Seed; Moutarde blanche, Fr. Cod.; Semen Erucae, P. G.; Weisser Senfsamen, Weisser Senf, G,; Senape bianca, It.; Mostaza blanca, Sp.
Neither black nor white mustard is any longer official in the British Pharmacopoeia.
Yellow or white mustard is a native of Europe and is extensively cultivated, being occasionally spontaneous, in the United States. The commercial supplies are obtained from England, Holland, Germany and California.
Properties.—The official description of white mustard is as follows: "Sub-globular, from 1.5 to 2.5 mm. in diameter; testa yellowish, nearly smooth; embryo yellowish, oily, with two large cotyledons; inodorous, taste mildly pungent, acrid. The powder is light yellowish or pale brownish-yellow, developing a slight odor when moistened; when examined under the microscope it exhibits numerous tissues of the embryo containing small aleurone grains and a fixed oil, the latter forming in large globules on the addition of hydrated chloral T.S.; fragments of seedcoat comparatively few, nearly colorless, with small, characteristic stone cells and large epidermal cells, the outer walls being mucilaginous. The powder contains few or no starch grains. White Mustard does not yield allyl isothiocyanate upon distillation with steam (distinction from Black Mustard). White Mustard yields not more than 9 per cent. of ash." U. S.
For an illustrated monograph on the pharmacognosy of white mustard, see Winton and Moeller, "Microscopy of Vegetable Foods." The only adulterant of white mustard are the seeds of the white Indian colza, obtained from Brassica campestris Sarson (L.) Prain. They are distinguished in having a more pronounced ridge over the radicle. Under the microscope the seeds have an indistinct epidermis, the collenchymatous subepidermal layer is wanting, and the palisade cells are quite large compared with white mustard. For further information see Sinapis Nigra.