Crocus, B.P. Saffron.
Saffron, or hay saffron, consists of the dried stigmas and the tops of the styles of Crocus sativus, Linn. (N.O. Irideae), a plant cultivated in Spain, and to a less extent in France, Austria, and Italy. The flowers are collected in the autumn, and the stigmas and upper parts of the styles are separated and dried. The drug occurs in loosely matted, dark reddish-brown masses, composed of single stigmas or three stigmas attached to a short portion of the yellow style. Floated on water the stigmas are seen to be about 25 millimetres long, and of a characteristic tubular shape, irregularly notched at the top. Saffron is flexible and unctuous to the touch when fresh, becoming brittle when quite dry. It has a characteristic odour and bitterish taste. It should not lose more than 12.5 per cent. of moisture when dried at 100°. It contains about 13 per cent. of water-soluble matter, and yields about 6 per cent. of ash. The high price of saffron has led to its adulteration in the following ways:—
- By substituting some substance for the stigmas, such as the florets of the safflower, Carthamus tinctorius, Linn., the stamens or portions of the perianth of the saffron crocus or of other plants, calendula florets, etc., etc., all of which may be detected by examining the drug after expansion on water.
- By recolouring exhausted saffron with aniline dyes, logwood, etc., which may be detected by their solubility in various liquids, such as ether, petroleum spirit, etc., and by the colour they impart to the water on which the saffron is thrown.
- By increasing the weight of the drug by the addition of various substances. Oil, which also improves the appearance, may be detected by the stain left when the drug is pressed between thin sheets of paper; other substances by the percentages of ash, moisture, and water-soluble matter; or by deflagration on incineration.
Constituents.—Saffron contains about 1 per cent. of volatile oil, an amorphous red colouring matter, crocin or polychroit (resembling and probably identical with carotin), and a colourless, crystalline, bitter principle, picrocrocin. Crocin, like carotin, is coloured deep blue by concentrated sulphuric acid, and green by nitric acid.
Action and Uses.—Saffron is used almost entirely for its colouring and flavouring properties. Tinctura Croci is a permanent preparation of saffron, preserving both its colour and flavour. Syrupus Croci, as commonly made, has a brilliant colour when fresh, but it deposits on keeping, and Glycerinum Croci, an excellent colouring agent in the proportion of 6 decimils (0.6 milliliters) to 30 mils (10 minims to 1 ounce) of mixture, is to be preferred.
- Glycerinum Croci, B.P.C.—GLYCERIN OF SAFFRON. 1 in 40.
- Used to prepare Syrupus Croci, and as a colouring and flavouring agent for mixtures, 3 to 6 decimils (0.3 to 0.6 milliliters) (5 to 10 minims) being added to 30 mils (1 fluid ounce) of mixture. It should be kept in well-stoppered bottles, filled so as to prevent access of air and consequent loss of colour by oxidation.
- Syrupus Croci, B.P.C.—SYRUP OF SAFFRON. 1 (glycerin of saffron) in 8.
- Used as a colouring and flavouring agent, 4 mils (1 fluid drachm) to 30 mils (1 fluid ounce) of mixture.
- Tinctura Croci, B.P.—TINCTURE OF SAFFRON.
- Saffron, 5; alcohol (60 per cent.), 100. Prepared by the maceration process. Tincture of saffron is used chiefly as a colouring agent. It should be kept in well-stoppered bottles, filled to prevent access of air and consequent loss of colour by oxidation. Dose.—3 to 10 decimils (0.3 to 1.0 milliliters) (5 to 15 minims).