BREAD

If rapid, acetous; so that to effect that kind of fermentation requisite for the production of the best bread, a ferment is added, which is either leaven or dough which is already in a fermenting state, and which tends to accelerate the proce in the ma to which it is added; or yeast, the peculiar matter which collects in the form of scum upon beer in the act of fermentation. Of these ferments leaven is slow and uncertain in its effect, and gives a sour and often slightly putrid flavour. Yeast is more effective; and when clean and good, it rapidly induces panary fermentation; but it is often bitter, and sometimes has a peculiarly disagreeable smell and taste. All, then, that is e ential to make a loaf of bread is dbugh to which a certain quantity of yeast has been added. This mixture is put mto any convenient mould or form, or merely shaped into one ma ; and after having l>een kept for a short time in rather » warm place, so that fermentation may have begun, it is subjected to the proce of baking in a proper oven. Carbonic acid is generated; and the viscidity or texture of the dough preventing the immediate escape of that gas, the whole ma is puffed Up by it, and a light porous bread is the result. Along with the carbonic acid traces of alcohol are at the same time produced, but so insignificant and impure as not to be worth notice; hence the attempts which have been made to collect it upon the large scale have entirely failed in an economical point of view. Other flour besides that of wheat will, under similar circumstances, undergo panary fermentation; but the result is a heavy, unpalatable, and often indigestible bread; so that the addition of a certain quantity of wheat flour is almost always had recourse to. It is the gluten in wheat which thus peculiarly fits it for the manufacture of bread, chiefly in consequence of the tough and elastic viscidity which it confers upon the dough. It is well known that home-made bread and baker's bread are two very different things: the former is usually sweeter, lighter, and more retentive of moisture: the latter, if eaten soon after it has cooled, is pleasant and spongy; but if kept for more than two or three days, it becomes harsh and unpalatable. The cause of this difference may perhaps be obvious from the following details of the operations of the wholesale baker. In making his dough he takes the water, or part of it, which he intends to use, and having slightly warmed it, di olves in it a certain portion of salt; then he adds the yeast, and then a certain quantity of flour. This mixture is set aside in a warm place, where it soon begins to ferment. This proce is called setting the sponge; and according to the relation which the water in it bears to the whole quantity to be used in the dough, it is called whole, half, or quartern sponge. The evolution of carbonic acid causes the sponge to heave and swell; and when the surface bursts it subsides, and then swells again, and so on; but the baker is careful to use it before this fermentation has communicated sourne to the ma . He then adds to the sponge the remaining quantity of flour, water, and salt which may be required to form dough of proper quality and consistence, and incorporates the whole by long and laborious kneadings till the entire ma acquires uniformity, and is so tough and elastic as to bear the pre ure of the hand without adhering to it. It is then left for a few hours, during which fermentation goes on; and the inflated ma is again kneaded, so as to break down any lumps or portions which had accidentally escaped diffbsion in the first operation, and to confer perfect uniformity on the whole. The dough is then weighed out into loaves, which are shaped, and put aside in a warm place for an hour or two, during which they swell up to about double their original size; they are then put into the oven and baked; during which operation they again enlarge considerably in bulk, in consequence of the dilatation of the previously generated carbonic acid pent up in the dough; for, as soon as the ma is exposed to the heat of the oven, the fermentation is put an end to. If we compare the baked loaf with the flour of which it is composed, we shall find that panary fermentation has produced a considerable change in the latter. The gluten and the starch, which (exclusive of a trace of sugar) were the components of the flour, have mutually acted upon and altered each other; the toughne and viscidity of the gluten is gone, and the starch no longer forms a gelatinous mixture with hot water; a little sugar is generally formed, as well as alcohol; but the principal cause of the change in the characters of the flour 18 the evolution of carbon and of oxygen in the form of carbonic acid, the production of which is independent of the presence of external oxygen (or of air). Small quantities of alum are also, it is said, invariably used by the London bakers, with the view of whitening or bleaching the bread; for it may be observed, that whatever may be the quality of the flour which is used, home-made bread is always of a comparatively dingy hue. According to Mr. Accum {On the Adulteration of Food), the requisite quantity of alum for this purpose 100 BRECCIA. depends upon the quality of the flour. The mealman, he says, makes different sorts of flour from the same kind of grain. The best flour is chiefly used for biscuits and pastry, and the inferior kinds for bread. In London no fewer than six kinds of wheaten flour are brought into the market; they are called fine flour, seconds, middlings, coarse middlings, and twenty-penny. Beans and peas are also, according to the same authority, frequently ground up with London flour. The smallest quantity of alum used is from three to four ounces to the sack of flour of 240 pounds. Another article occasio'iiall;^ employed in bread making is carbonate of ammonia. As it is wholly di ipated by the heat of the oven, none remains in the baked loaf. Jt renders the bread light, and perhaps neutralizes any acid that may have been formed (exclusive of carbonic acid); but it is too dear to be much employed. To some kind of biscuits it gives a peculiar shortne , and a few of the most celebrated manufacturers use it largely. The French chemists have accused the bakers of employing sulphate of copper or blue vitriol, for the purpose of improving the colour of the bread; but so dangerous and easily detected an addition can scarcely be supposed to be common. According to Mr. E. Davy, bread, especially that of indifferent flour, is materially improved by the addition of a little carbonate of magnesia, in the proportion of twenty to thirty grains to the pound of flour; It requires to be very intimately mixed with the dough. The most nefarious adulteration of bread consists, however, in the addition of certain insipid and colourle earthy substances, with a view of increasing its weight; such as pipe-clay, porcelain-clay, chalk, and plaister of Paris. These, however, are probably very rarely resorted to; though in one instance the writer of this article had occasion to examine a quantity of biscuits, which were adulterated with gypsum to the amount of 10 per cent. BREAK. (Teut. brache.) In Architecture, any projection from the general surface of a building. BREA'KERS. Waves that break, or fall over, from the shallowne of the water. In a gale, the tops of the seas generally break in this way more or le , from the progre ive motion of the water at the surface before the wind, which is exceedingly dangerous for open boats. This is never confounded with the falling over of the whole wave, as the surf falls over on the beach. BREA'KING JOINT. In Architecture, that disposition of stones and bricks in their courses by which vertical joints are not allowed to fall over each other. See Diagrams to Bond, English and Flemish. BREAKWA'TER. An artificial bank of stones, or the hull of a ve el, sunk to break the sea before its entrance into a roadstead or harbour. The breakwater at Plymouth is a great work of this kind. It is built acro the sound, which it completely defends from a very heavy sea from the channel in south-westerly winds, and which formerly caused the lo of many ships. It is composed of large stones dropt from ve els constructed for the purpose. The sea, which for a time offers serious obstacles to the construction, works the stones together, and washes up shingle and sand, which, with the growth of sea-weed, consolidate the whole. The outer mole of the harbour of Civita Vecchia, still in good repair, was formed by the Emperor Trajan exactly in the same way as the breakwater at Plymouth. (Plinii Epist. lib. vi. ep. 31.) The breakwater at Cherbourg, constructed by Napoleon, is one of the greatest modern works of this cla . BREAM. The name of a soft-finned fish, common it many of the lakes and rivers of England, and one that breeds freely and thrives in ponds, if there be suflicient depth of water. It is the type of a particular subgenus of the Carp family {Cyprinidte), which Cuvier has characterized under the name of Abramis, See Abramis. BREA'MING. In Nautical language, signifies cleaning the bottom of a ve el by fire. When the ve el is aground, fire being applied to the bottom loosens the pitch, or composition of sulphur and tallow, with which the bottom is sometimes covered to defend it from the worms, and which is then scraped off, together with the barnacles, gra , weeds, . that adhere to it. BREA'STING. Breasting up a hedge is cutting the face of it on one side, so as to lay bare the principal upright stems of the plants. BREAST PLOUGH. A kind of spade or shovel, with a cro piece at the extremity of the handle, which is applied to the breast, and by which the operator skims off a thin slice of turf from a gra y surface, as if he were ploughing. Turf thus obtained is chiefly used in thatching. BREA'STSUMMER. (From Sax. bneofr, and summer; aua;re, trabs summar i a?) In Architecture, a beam whicn supports an exterior wall, the beam itself being carried by wooden or iron posts. BREAST-WORK. In Fortification, an elevation of earth thrown up round a fortified place to protect the garrison from the enemy's fire. BRE'CCIA. (It.) A rock composed of an agglutination of angular fragments. Page 180