Online Encyclopedia

nucleus or hilum surrounded by layers arranged concentrically or excentrically, and the relations of hilum and layers are the most distinctive features of individual starches (see H. See also:

Galt, Microscopy of the Starches, 1900). Starch consists of a See also:

white or yellowish-white glistening See also:

POWDER (through O. Fr. puldre, modern poudre, from Lat. pulvis, pulveris, dust)

powder. It is only slightly acted on by See also:

COLD (in O. Eng. cald and ceald, a word coming ultimately from a root cognate with the Lat. gelu, gelidus, and common in the Teutonic languages, which usually have two distinct forms for the substantive and the adjective, cf. Ger. Kolte, kalt, Dutch koude

cold See also:

WATER

water, but under the influence of See also:

HEAT (0. E. haktu, which like " hot," Old Eng. hat, is from the Teutonic type haita, hit, to be hot; cf. Ger. hitze, heiss; Dutch, hitte, heet, &c.)

heat in water it swells up, forming according to the proportions of starch and water a clouded opalescent See also:

PASTE (O. Fr. paste, modern pate, Late Lat. pasta, whence also in Span., Port. and Ital., from Gr. 1r&vrrl or 1raara, barley porridge, or salted pottage, ir&ao'ety, to sprinkle with salt)

paste. The soluble portion is called granulose, and the insoluble starch-See also:

CELLULOSE

cellulose; from the aqueous See also:

SOLUTION (from Lat. solvere, to loosen, dissolve)

solution See also:

ALCOHOL

alcohol precipitates soluble starch. See also:

IODINE (symbol I, atomic weight '26.92)

Iodine acts on it in water, producing a brilliant See also:

BLUE (common in different forms to most European languages)

blue coloration, this reaction forming a very delicate and characteristic test. The See also:

COLOUR (Lat. color, connected with celare, to hide, the root meaning, therefore, being that of a covering)

colour disappears on See also:

HEATING

heating, but is recovered when the mixture is cold.

Diastase and dilute boiling sulphuric See also:

ACID (from the Lat. root ac-, sharp; acere, to be sour)

acid convert starch into a form soluble in hot water, whence it passes into a See also:

SERIES (a Latin word from serere, to join)

series of easily soluble dextrins, and finally into the See also:

CONDITION (Lat. condicio, from condicere, to agree upon, arrange; not connected with conditio, from condere, conditum, to put together)

condition of the sugars, dextrose and maltase. Chemically, starch is a See also:

CARBOHYDRATE

carbohydrate with the See also:

formula (See also:

C6H,0O5),,, where n is four or more. As an economic product starch in its See also:

SEPARATE

separate condition is a most important alimentary substance, the See also:

CHIEF (from Fr. chef, head, Lat. caput)

chief pure See also:

food starches being See also:

ARROWROOT

arrowroot, sago, See also:

TAPIOCA (a native Brazilian word)

tapioca and cornflour. In its combined condition, in cereals, &c., starch is a useful nutritive See also:

ELEMENT (Lat. elementum)

element. In its other See also:

INDUSTRIAL

industrial relations starch is used: (1) directly, as a thickening material in See also:

CALICO

calico See also:

PRINTING (from Lat. imprimere, O. Fr. empreindre)

printing, for the dressing and See also:

FINISHING

finishing of many textiles, for See also:

LAUNDRY

laundry purposes, adhesive paste, and powder; and (2) indirectly, for the preparation of dextrin and See also:

BRITISH

British See also:

GUM (Fr. gomme, Lat. gommi, Gr. Kµµ1, possibly a Coptic word; distinguish " gum," the fleshy covering of the base of a tooth, in O. Eng. gbma, palate, cf. Ger. Gaumen, roof of the mouth; the ultimate origin is probably the root gha, to open wide, seen in

gum and starch See also:

SUGAR

sugar. See also:

INDIAN

Indian See also:

corn, See also:

wheat and See also:

rice starch are principally employed for the See also:

DIRECT

direct applications; and for the dextrin and starch-sugar manufacture See also:

potato starch is almost exclusively selected. In the preparation of starch the See also:

OBJECT

object of the manufacturer is to burst the vegetable cell walls, to liberate the starch granules, and to See also:

FREE

free them from the other cell contents with which they are associated. When, as in the See also:

case of the potato, the associated cell contents, &c., are readily separated by solution and levigation the manufacture is exceedingly See also:

SIMPLE

simple. Potato starch is prepared principally by carefully washing the potatoes and in a See also:

KIND (O. E. ge-cynde, from the same root as is seen in " kin," supra)

kind of rasping See also:

machine reducing them to a See also:

FINE

fine pulp, which is deposited in water as raw starch. The impurities of this starch—cellulose, albuminoids, fragments of potato, &c.—are separated by washing it in fine See also:

SIEVES

sieves, through the meshes of which the pure starch alone passes. The sieves are. variously formed, some revolving, others moving horizontally or in such manner as to keep the material in agitation. The starch is then received in tanks, in which it settles, and so separates from the soluble albuminoids and salts of the potatoes.

(The See also:

WASTE (O. Fr. wast, guast, gast, gaste; Lat. vastus, vast, desolate)

waste pulp which passes over the See also:

SIEVE (O.E. sife, older sibi, cf. Dutch zeef, Ger. Sieb; from the subst. comes O.E. siftan, to sift)

sieve is pressed, dried quickly, and sold as a See also:

low-grade See also:

CATTLE (Norman Fr. catel, from Late Lat. capitale, wealth or property, a word applied in the feudal system to movable property and particularly to live stock, and surviving in its wider meaning as " chattel " or " chattle ")

cattle food.) The settling of the starch is much retarded by the dissolved albuminoids, and to hasten the separation small quantities of See also:

ALUM

alum or sulphuric acid are employed. Alum coagulates the albumen and to that extent contaminates the starch, while the acid acts on the starch itself and is difficult of neutralization. After the starch has settled, the See also:

brown-coloured supernatant liquor is See also:

DRAWN

drawn off and the starch again washed either in tanks or in a centrifugal machine. Finally it is dried by spreading it in layers over porous bricks (a See also:

PROCESS

process not required in the case of starch washed in a centrifugal machine) and by exposure to the See also:

air, after which it still retains a large proportion of water, but is in a condition for making dextrin or starch-sugar. For further drying it is ground to a rough powder, and dried thoroughly in a hot chamber, then reduced to a powder and sifted. Potato starch is also made by a " rotting " process, in which potatoes are reduced to a pulp by slicing and are then heaped up till See also:

FERMENTATION

fermentation takes See also:

PLACE (through Fr. from Lat. platea, street; Gr. IrAar6s, wide)

place; See also:

ion lb of potatoes yield 15–16 lb of dry starch. In dealing with the starches of the cereals, there is greater difficulty, owing to the presence of See also:

GLUTEN

gluten, which with water forms a tough elastic body difficult of solution and removal. The difficulty is experienced in greatest measure in dealing with wheat, which contains a large proportion of gluten. Wheat starch is separated in two different ways: (1) the fermentation method, which is the See also:

ORIGINAL

original process, and (2) by See also:

MECHANICAL

mechanical means without preliminary fermentation. In the fermentation process whole wheat or wheaten See also:

MEAL

meal is softened and swollen by soaking in water. Wheat grains are, in this condition, ground, and the pulp, mixed to a thickish fluid with water, is placed in tanks, where it ferments, developing acids which dissolve the gummy constituents of the wheat, with See also:

PART

part of the gluten, and render the whole less tenacious. After full fermentation, the period of which varies with the See also:

WEATHER (O. Eng. weder; the word is common to Teutonic languages; cf. Du. weder, Dan. veir, Icel. ve8r, and Ger. Wetter and Gewitter, storm; the root is wa- to blow, from which is derived " wind ")

weather and the process employed, the starch is separated in a washing See also:

DRUM (early forms drome or dromme, a word common to many Teut. languages, cf. Dan. tromme, Ger. Trommel: the word is ultimately the same as " trumpet," and is probably onomatopoeic in origin; it appears late in Eng. about the middle of the 16th century)

drum.

It is subsequently washed with water, which dissolves out the gluten, the starch settling in two layers—one comparatively pure, the other mixed with gluten and some branny particles. These layers are separated, the second undergoing further washing to remove the gluten, &c., and the remaining operations are analogous to those employed in the preparation of potato-starch. By the mechanical process wheaten See also:

FLOUR

flour is kneaded into a stiff paste, which, after resting for an See also:

HOUR

hour or two, is washed over a fine sieve so See also:

long as the water passing off continues milky, whereby the starch is liberated and the greater part of the gluten retained as a gluey elastic See also:

mass in the sieve. The starch is subsequently purified by fermentation, washing and treatment in centrifugal See also:

MACHINES

machines. The gluten thus preserved is a useful food for diabetic patients, and is made with flour into artificial See also:

MACARONI (from dialectic Ital. maccare, to bruise or crush)

macaroni and pastes, besides being valuable for other industrial purposes. The fermentation process gives about 59 lb of starch and 11 of See also:

BRAN

bran from 10o lb of wheat, whilst the mechanical process gives about 55 lb of starch and 12 of gluten. See also:

MAIZE, or INDIAN CORN

Maize (Indian corn) starch is obtained by analogous processes, but, the proportion of gluten in the See also:

GRAIN (derived through the French from Lat. granum, seed, from an Aryan root meaning " to wear down," which also appears in the common Teutonic word " corn ")

grain being smaller and less tenacious in its nature, the operations, whether chemical or mechanical, See also:

PRESENT

present fewer difficulties. Under one method the separation of maize starch is facilitated by steeping, swelling and softening the grain in a weak solution of See also:

CAUSTIC (Gr. rcavvraubs, burning)

caustic soda, and favourable results are also obtained by a process in which the pulp from the crushing See also:

mill is treated with water acidulated with sulphurous acid. In the preparation of rice-starch a weak solution of caustic soda is also employed for softening and swelling the grain. It is then washed with pure water, dried, ground and sifted, and again treated with alkaline water, by which the whole of the nitrogenous constituents are taken up in soluble form. ,An acid process for obtaining rice-starch is also employed, under which the grain, swollen and ground, is treated repeatedly with a solution of hydrochloric acid, which also dissolves away the non-starchy constituents of the grain. The yield is about 85 lb per See also:

LOO (formerly called " Lanterloo," Fr. lanturlu, the refrain of a popular 17th-century song)

loo of rice.

Laundry starches are principally made from rice and from See also:

PULSE

pulse. See O. Saare, See also:

Die Fabrikation der Kartoffelstarke (1897).

End of Article: STARCH

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