Barley, by being converted into malt, generally increases two or three per cent. in bulk ; and loses, at an average, about 20 per cent. in weight, of which 12 are ascribed to kiln-drying, and consist of water, which the barley would have lost had it been exposed to the same temperature : so that the real loss does not exceed 8 per cent. The roots appear, from the process, to be formed chiefly from the mucila ginous and glutinous parts of the kernel. The starch is not employed in their formation, but undergoes a change, intended, no doubt, to fit it for the future nourishment of the plumule. It acquires a sweetish taste, and the property of forming a transparent solution with hot water. In short, it approaches somewhat to the nature of sugar, and is probably the same with the sugar into which starch is converted by boiling it with diluted sulphuric acid.
The following are the results of Dr. Thomson's analysis of barley and the pale malt made from it :— In brewing ale, porter, and table-beer, three different kinds of malt are employed, which are known as pale or amber malt, brown or blown malt, and roasted or black malt, sometimes called patent malt. The pale or amber malt yields the saccharine or fermentable extract ; the brown malt is not fermentable, but is employed to impart flavour ; and the roasted malt is employed, instead of burnt sugar, merely to give colouring matter to porter. In the brown and roasted malts the sugar appears to be entirely converted into gum and colouring and extractive matters ; and hence they are incapable of undergoing fer mentation. The brown malt is subjected to a higher temperature in drying than the pale malt, and by a still further exposure to heat in revolving cylinders or roasters it is converted into black or patent malt.
Most of the changes which have occurred in the malt trade have been due to the peculiar manner in which the product is subjected to duty. Mr. Tyzard introduced a new arrangement of malting apparatus in 1852; and Mr. Plomley, in 1858, devised a mode of making the heat act upon the surface of the malt as well as upon the bottom, in drying; but the foregoing details will suffice to show the general principle on which the operation is conducted. The excise duty has had the effect both of limiting the quantity made, and of checking any improvements in the making. The malt-duty began in England in 1697, in Scotland
in 1713, and in Ireland in 1783. In the hundred years from 1716 to 1816 there was scarcely any increase in the quantity of malt made in England ; the measure never departing far from 24 million bushels in a year. This stationary condition, at a time when population was steadily increasing, was attributed partly to an increase in the taste for tea and coffee, but chiefly to the effect of duty and restriction. This duty rose gradually from 6d. in 1702, to 4s. 6d. in 1804; it is now a fraction under 29. 9d. Since 1830, the quantity paying duty has varied from about 30 to 40 million buihels. In 1859 it was 40,406,447, besides 546,743 bushels exempted from duty on various grounds. The price has varied from 23. 6d. to 108. 6d. per bushel, during a century and a half, the average being about 4s. 6d. The excise regulations were so very stringent in past years, that the maltsters scarcely knew in what manner to conduct their business. An act, passed to regulate the trade in 1827, contained no fewer than 83 clauses, many of which were difficult of interpretation ; more than 100 penalties under it were enforced in three years, amounting to a sum of 13,500/. This was replaced by a better statute in 1830, with numerous but intelligible clauses relating to the gauging of cisterns, the wetting of the malt, emptying of the cisterns, the gauging of the malt when In the kiln, &c. Another act was passed in 1647, still further to facilitate the operations of the malteter without lesetenIng the duty. The Commissioners of Inland Revenue, in a report drawn up in 1857, stated that they were much puultel by attempts at fraud made by some of the less scrupulous masters. One fraud consisted In compressing the grain in the couch, so as to lessen the measure by which the duty was charged. Another fraud was that of mixing raw grain with malt, roasting the two together, and selling the mixture to the brewers as malt. This last trick has been eQunteracted by an order, according to which grain Is to be considered as still nnmalted unless the plumule extends half length of the gran ; and by compelling brewers to crush their malt in a way which would not he applicable to unmated grain.