Starch is a constituent in the saccharine group of organic substances. In this country, it is now mostly obtained from corn, and a smaller quantity from wheat; and it also abounds in potatoes, rice, and most of the cereals. Tapioca, sago, and arrow-root, are peculiar forms of starch, obtained from the roots of certain woody plants. It is obtained by soaking the grain and then grinding it; passing it through sieves, in company with a large quantity of water, to separate the bran; and then allowing the starch to settle in large vats filled with water. Afterward it is cut into large cubical masses, and kiln-dried at a temperature of about 125 deg. Fahrenheit.
The appearance of starch is well known. It consists of a mass of small granules, each with a membranous covering. It is not soluble in cold water, alcohol, ether, or the oils. Boiling water breaks down the membranous envelope, and then it is so effectually suspended in water as to appear as if it were dissolved. Trituration and heat will also break down these membranes, so that their contents can be suspended in cold water. By roasting for three hours at a temperature of 300° F., it is converted into a brittle, yellowish-brown mass, readily soluble in cold water, and used as a paste under the name of British Gum. By boiling in very dilute sulphuric acid, all starches are slowly converted into a species of grape-sugar, (see Alcohol) and fermentation with the dextrine of wheat malt will effect the same change, more rapidly. When thus converted into sugar, boiling with strong nitric acid will form it into the oxalic acid of commerce.
Properties and Uses: Boiled starch is mostly used for laundry purposes, to give stiffness to cotton fabrics; and as a paste in the laboratory. It is an excellent article of nutrition, with almost pure demulcent properties; and physicians would find much advantage in turning the attention of patients to it as one of the lightest articles of diet, suitable for children and adults in bowel complaints, in convalescence from parturition, typhoid, and a great many other cases. One of the most elegant dishes made from it is by mixing three tablespoonfuls of the pulverized starch, (prepared by Mr. George Fox, 87 Columbia Street, Cincinnati,) into a quart of milk, and boiling for three minutes with a tablespoonful of sugar. It may be flavored with lemon or vanilla; and when cold, forms a nice jelly. Eggs may be added to it for a heartier dish. It is preferable to arrow-root and sago.
Medically, boiled starch is soothing and very slightly astringent to mucous surfaces. A trifle is a desirable addition to the milk of children who nurse from the bottle. It is used mostly as a mucilaginous vehicle for suspending powders, and as a demulcent ingredient for injections. Combined with glycerin, it makes an excellent soothing appliance, as well as a good vehicle for conveying powdered drugs. The dry powder may be dusted upon chafed surfaces, and upon parts troubled with erysipelas; and is a fair absorbent of irritating secretions.
The Physiomedical Dispensatory, 1869, was written by William Cook, M.D.
It was scanned by Paul Bergner at http://medherb.com