Page:Encyclopædia Britannica, Ninth Edition, v. 4.djvu/310

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266
BREWING

and again weighed the difference would show the weight of fermentable matter extracted from the malt. His instrument, therefore, was graduated so as to show one degree for each pound that a barrel of wort weighed more than a barrel of water. He does not, however, allow for the displacement of a certain quantity of water by the saccharine matter dissolved in it; consequently, his instrument is not quite correct. The saccharometer of Dring and Fage and that of Long, which are both on the same principle as Richardson s, are adjusted so as to allow for this inaccuracy ; for example, if a gallon of sugar, weighing 16 ℔, be added to 35 gallons of water (together making one barrel imperial measure), their instruments show in this infusion, at 60° Fahr., the excess above that of distilled water, which, in this instance, is 6 ℔ gravity ; thus we have a barrel of wort, weighing 366 ℔, composed of water 35 gallons, and saccharine matter 16 ℔. The Excise make their calculations by Allan and Bate's instruments, which are constructed on the principle of indicating the specific gravity of the wort,—that of distilled water, which is the standard of weight by which all substances have to be compared, being reckoned 1000. It is, however, easy to change the reckoning of the one to the other. Should we wish to reduce the specific gravity indicated by Allan's or Bate's instruments, we have only to divide the specific gravity by 2.77 ; or if we wish to convert the indication of Dring and Fage's scale into specific gravities

we multiply by the same factor.

Barley is the seed of several species of Hordeum, and be longs to the tribe of grasses, called by botanists Graminacece. It has been cultivated from the earliest times. The species most used for malting purposes are the long-eared or two- rowed barley (Hordeum distickum], and the Hordeum hexastichon, commonly called bere or bigg. This, in con sequence of its being more hardy and ripening more rapidly, is cultivated in Scotland and Ireland. The variety of the two-rowed most in repute is the Chevalier. This was introduced early in the present century by the rector of Stonham, in Suffolk, after whom it was named, and was the result of careful cultivation, Mr Chevalier saw some fine specimens of two-eared barley growing on a manure heap, had them saved, and cultivated them for several years, selecting only the soundest and largest seeds, until the Chevalier barley became famous and commanded large prices. The land in Great Britain suitable to the growth of the finest grain for malting is limited, the most favour able districts being Suffolk, Norfolk, and parts of Essex and Herts. It is, of course, cultivated in all other counties, but not to the same extent. From the Agricultural Returns of Great Britain, presented to Parliament, we find that in the year 1870, there were 2,600,000 acres under barley, which, if taken together, would form a block 1/6th larger than the counties of Suffolk and Norfolk. Taking the average yield at 32 bushels per acre, the total is 83,000,000 bushels, or more than 10,000,000 quarters. Of this, 50,000,000 bushels were converted into malt, and 4,000,000 used by the distillers. Farmers find by experience that some land is not fit for the growth of this cereal, and maltsters that if it is grown on certain soils it will not make good malt. Light calcareous or friable gravelly dry soil is the best. Rich loamy soil produces an excellent crop, and sandy soil, when well manured, answers; but cold clayey land, even when well drained, will not produce the best malting barley It is a most precarious crop, requires but little moisture, and a wet season is fatal to it. When it is in full ear rain, or even heavy dew, will break the stalk, and if wet continues for two or three days the ears on the ground begin to grow, get stained, and become quite unfit for malting. It should remain in the stack at least a month to season. If "got up" damp, it is liable to generate excessive heat, in which case the growing power of the germ is destroyed, and the grain rendered useless for malting purposes. Good barley should have a thin, clean, wrinkled husk, closely adhering to a plump well-fed kernel, which, when broken, appears white and sweet, with a germ full, and of a pale yellow colour. It is of all cereals the best adapted for malting, containing as it does more starch and far less gluten than other grain, and about 7 per cent, of ready-formed grape-sugar. Its specific gravity is from 1.280 to 1.333, that of malt 1.200. A bushel of barley weighs^between 53 ℔ and 58 ℔, depending on climate, soil, and harvest ; the same quantity of bere or bigg weighs from 47 ℔ to 51 ℔. It cannot well be too heavy, as it gives a corresponding gravity to the malt, providing it be mellow, thin-skinned, and not steely. The cuticle, or husk, forms nearly 1/6th of the weight of barley, and between 1/4th and 1/5th in bigg. According to Einhoff, 1000 parts of barley meal contain 720 of starch, 100 of water, 68 of fibrous or ligneous matter, 56 of sugar, 50 of mucilage, 36.6 of gluten, 12.3 of vegetable matter, and 2.5 of phosphate of lime. Hermbstädt gives the following percentages as the mean of ten analyses of barley made by him:—

Water 10.48
Husk 11.59
Gluten 4.91
Albumen 0.35
Starch 60.50
Sugar 4.66
Gum 4.50
Oil 0.35
Soluble phosphates, &c. 0.36
Loss 2.30
———
100.00

Great care must be taken when buying for malting, for sometimes .the grain is doctored by kiln-bleaching or dried at too great a heat. Several samples, too, may be mixed, in which case they will not grow regularly, as heavier barley generally requires to be longer in steep. Corns broken by the drum of the thrashing-machine being set too close spoil a sample; those cut into sections will not germinate, but in warm weather putrefy, as is evident from their blue-grey and mouldy appearance, and offensive smell whilst germinating. A good buyer will, by the use of a skilful hand, estimate very closely the weight per bushel in bulk ; his eye will tell him if the grain has been cut before being ripe, in which case there will be a variety in the colour of the barley-corns, some being bright, and some a dead greyish yellow. In consequence of being sown in spring, and not undergoing the equalizing tendency of winter, barley is of all grain the most liable to ripen in a patchy manner, and not come to perfection simultaneously. The buyer has also to judge if it has been heated or "mow-burnt" while lying in the field after being cut, or in the stack ; this it is apt to do in showery weather, or when the crop of clover, which is generally sown with or soon after the barley, is luxuriant. In this case the grain is apt to sprout, and as the process of malting is as near as can be a natural vegetation, barley once sprouted is useless to the maltster.

Malting.—The word malt has been variously derived

from roots that have respectively the meanings of grinding, soaking, and rotting. The last derivation, corresponding to the humor ex hordeo corruptus of Tacitus (Germ. 23), is the most probable. Malting consists in steeping the grain in water to supply moisture enough to cause it to germinate, and when the growth is sufficiently advanced, stopping it by drying the grain on a kiln. Before explaining the process of malting we must describe the construction of the seed, and see the chemical changes that take place. A grain of barley is composed of several parts—the inner and outer husks, the cotyledon, the corcule (which includes the plumule

or future stem and the rostel), the investing membrane,