Bread.

Bread. The earliest and most primitive way of making bread was to soak the grain in water, subject it to pressure, and then dry it by natural or artificial heat. An improvement upon this was to pound or bray the grain in a mortar, or between two flat stones, before moistening and heating. A rather more elaborate bruising or grinding of the grain leads to such simple forms of bread as the oat-cakes of Scotland, which are prepared by moistening oatmeal (coarsely ground oats) with water containing some common salt, kneading with the hands upon a baking-board, rolling the mass into a thin sheet, and ultimately heating before a good fire, or on an iron plate called a girdle, which is suspended above the fire. In a similar manner, the barley-meal and pease-meal bannocks of Scotland are prepared; and in the East Indies (especially the Punjab and Afghanistan), as well as in Scotland, flour is kneaded with water, and rolled into thin sheets, as scones (although this term is usually applied to bread lightened with butter-milk and baking-soda.) The passover cakes of the Israelites were also prepared in this way. A similar preparation of wheat-flour, but where the sheet of dough is made much thicker, forms the dampers of Australia. The Indian corn-meal, kneaded with water and fired, affords the corn-bread of America. The kinds of bread referred to above are designated unleavened, as no leaven has been added to the dough to excite fermentation. No chemical change has therefore been produced except that the starch has been rendered more soluble by the process of baking. Even in the time of Moses, however, leaven was employed in making bread. It is held probable that the Egyptians were the first to use leaven; that the secret afterwards became known to the Greeks; and that the Greeks communicated the process to the Romans, who spread the invention far and wide in the northern countries during their campaigns.

The grain of wheat is generally employed in the manufacture of bread among the better classes and more advanced nations, though rye, barley, Indian corn, and rice are also extensively used. The average composition of the grain of wheat is:

The proportion of these ingredients, however, varies considerably. Much depends on soil and climate. Taken as a general rule, to which there are exceptions, the wheat becomes more starchy as we proceed southwards. The strongest foreign flours (i.e. those richest in gluten) are grown in Minnesota, Manitoba, Hungary, and Russia. Indian wheat usually furnishes a wcal flour. The principal constituents of wheat may be separated from each other without much difficulty. Thus, if wheat- flour be placed in a cloth-bag with the mouth well closed, and the whole introduced into a basin of water, and pressed by the fingers for some time, the starch is squeezed through the cloth as a fine white powder, and the gluten is left in the cloth as a viscid or sticky substance. Again, if wheat-flour be burned on a porcelain plate on a fire, or oven, or gas-lamp, till it can burn no longer, it leaves behind a small amount of ash or saline matter.

Previous to being employed in the fabrication of bread, the grain of wheat undergoes the process of milling, with the double object of reducing it to a fine state of division, and separating the more hard and indigestible parts (see MILL). During the grinding operations, the wheat as it passes from grain to flour nearly doubles its bulk. The products come from the dressing-machine divided into different qualities, a quarter of wheat yielding by some systems of milling:

In the making of bread in Great Britain, the flours are blended by the baker so as to produce bread of desired quality. In the making of good bread three things are absolutely requisite: flour or meal, yeast or leaven, and water containing salt. The Yeast (q.v.) or leaven is added to give a start to the Fermentation (q.v.) process, thereby supplying carbonic acid, which communicates a spongy or light texture to the bread. Leaven is the more primitive ferment, and is simply a portion of moistened flour or dough in which the putrefactive agencies have begun to work. It may be procured by allowing moistened flour to lie in a warm apartment (summer heat) for six or eight days, and when sufficiently formed, has an acid taste and reaction, and a somewhat fusty odour. When brought in contact with a new portion of flour and water, and incorporated therewith by kneading, it very quickly acts as a ferment, and develops partial fermentation in the whole. Hence it is that where leaven is used, it is customary to retain a portion of the leavened dough for the next baking. On the Continent, leaven is still very extensively employed, especially in districts far from breweries. In Britain, yeast is generally used as the ferment. There are three forms in common use—viz. 'brewers' yeast,' 'German compressed,' and 'patent.'

The materials being at hand, and the proper benches, utensils, and oven being within reach, the baker takes a quantity of water and adds to it the yeast and salt; after which the flour is added, and the whole thoroughly and laboriously kneaded together till it assumes a ropey consistence. It is then called the sponge, and is placed in a kneading-trough in a warm place, which is styled setting the sponge. In a short time, the yeast begins to act on the gluten, starch, and sugar of the flour, compelling the latter to pass into alcohol and carbonic acid gas in every part of the dough, which thereby becomes inflated with innumerable air cavities. When the fermentation has sufficiently advanced, the baker takes the sponge, adds more flour, water, and salt, a second time subjects the whole to a thorough process of kneading, and makes it into dough, after which he allows the mass to lie in a warm place for from one to two hours. The dough swells considerably from distension by gas, and is weighed out into lumps of the proper size, which are shaped into loaves, constituting the batch, or placed in tin pans, and allowed to lie for a short time till they get further distended. The oven has previously been heated to a temperature of at least 450° F., which is the lowest temperature at which bread can be baked, and ranging up to 572° F.; when it has been thoroughly cleaned out, the loaves are introduced, and the oven shut up. Until recent years bakers had not improved upon the method used in the bakeries of Pompeii—viz. by burning wood in the floor of the oven itself until the proper temperature had been reached, then cleaning out and introducing the loaves. Latterly, however, this somewhat inconvenient method has been improved upon, and many large bakeries are fitted with ovens heated either by flues, gas (regenerator), or superheated steam. The heat acts in dissipating much of the water from the dough, in distending the air cavities more fully, and in partially boiling the starch and gluten of the dough, and developing some gum from the starch. Indeed, though the temperature of the oven is much higher, yet the loaves beyond the mere crust are bathed in an atmosphere of steam, and are never heated above 215° F., as has been proved by direct experiments with the thermometer. One effect of the heat is to arrest any further Fermentation (q.v.; see also YEAST). After about one and a half hours' baking in the oven, the length of time being determined by the temperature, the loaves are withdrawn, and allowed to cool. The brown appearance of the crust of loaves, and the pleasant taste of the crusts, are due to the action of the heat on the starch and the formation of Dextrin (q.v.), a sort of gum. The number of quartern (4-lb.) loaves which a sack of flour weighing 280 lb. yields, is from 86 to 96 according to the strength of the flour. It will be apparent, therefore, that as 280 lb. of flour yield on an average 360 lb. of bread, a good deal more water must be present in the latter than in the former; and, indeed, ordinary good wheaten bread contains about 45 per cent. of water. This water is retained even after the loaf is apparently dry, and even mealy, as the gum and gluten have a great affinity for water.

Machinery has now superseded manual labour in many of the operations of bread-making. In a few of the largest bakeries the flours obtained from various sources are blended by passing through a sifting-machine, and are thence conveyed by a strap or endless screw to large bins. From these bins, when Parisian barm or brewers' yeast is used, the flour is drawn off into barrels or troughs in which the sponge has to be stirred. The stirring is usually performed by means of a vertical spindle provided with horizontal blades, which is made to revolve in a barrel or trough. At the proper time the sponge is emptied into a kneading-machine, the remainder of the water and salt is added, and a quantity of flour is drawn off from the bins sufficient to make the mass of the desired consistency. The whole is now thoroughly mixed into dough. This operation is completed in from five to ten minutes in batches which will turn out from one hundred to five hundred loaves. There are several kinds of kneading-machines in the market, but the two most commonly used are the 'Thomson' and the 'Pfleiderer' machines. They consist essentially of an iron trough provided with blades revolving in opposite directions. In the 'Thomson' machine the blades revolve upon the same axis, while those of the 'Pfleiderer' revolve upon different axes. As soon as the dough is thoroughly made, it is emptied into troughs, where it remains for an hour or two. It is then conveyed to a table and weighed out, and afterwards moulded into loaves as already detailed. There have been several attempts to make machines to divide and mould the dough into loaves, but these have not yet been perfected.

The baking business is chiefly carried on in shops of moderate dimensions, in which on an average perhaps twenty bags of flour are used per week, but in many large cities the factory system has been introduced. Some of these are on a very large scale, using 1000 to 2000 bags every week. From the nature of the industry, operations are principally carried on at night or early morning. In England till recently almost every family in the country baked its own bread, but the Scottish custom is gradually creeping in, of getting supplied by a baker from a neighbouring town.

The appearance which good wheaten bread ought to present is that of a vesicular or spongy mass, from which layers can be readily detached; and this, known to bakers as piled bread, is the best index of good, wholesome, and easily digested bread. When the layers cannot be detached, and the loaf cannot be crumbled down by the fingers into a coarse powder, or the fragments be thoroughly soaked and be readily diffused through water, but become a permanent tough mass of dough, the bread is imperfectly made.

Rye-bread is very extensively used in northern European countries, where the soil being sandy is admirably adapted for the growth of that grain. It yields a flour darker than wheat-flour. It is almost equal in nutritive value to wheaten bread. Barley and oats, which, when used as bread, are generally made into cakes or bannocks, possess also a composition not unlike wheat. Indian corn, which thrives luxuriantly on the American soil, and is largely used there for bread, as also to a considerable extent in the Old World, is little different from wheat in the proportion of its ingredients. Rice is occasionally employed in making bread, but it is not nearly so nutritious as wheat.

But although, with the exception of rice, the various kinds of grain do not sensibly differ in the amount of nutritious matter contained in the meal, yet there is a great difference as to the quality of yielding a light, spongy bread. In this respect the flour of wheat excels all others. This quality seems to depend upon the mechanical structure of the gluten of wheat, which gives a glutinous, sticky consistency to the dough, rendering it impervious to the carbonic acid gas formed in it during the fermentation, so that the gas thus imprisoned swells it up. The meal of other grains forms a more granular and less tenacious dough, which allows the gas to escape with more or less ease as it is formed. It is thus impossible to make a light spongy loaf of oatmeal, however finely it might be ground. In the case of whole-meal bread, or brown bread, the rough, hard particles of the bran interfere with the ordinary tenacious quality of wheaten flour, and make the dough slightly porous, so that much of the gas escapes, and thus this kind of bread is never so much raised as bread of fine flour.

Instead of raising the dough by the action of yeast, which decomposes a part of the flour and causes the loss of about 2 per cent., bicarbonate of soda and hydrochloric acid, or bicarbonate of soda and tartaric acid, are sometimes employed. The proportions by this process are 4 lb. of flour intimately mixed with 320 grains of bicarbonate of soda; to this is added a mixture of 35 ounces of water and 6½ fluid drachms of hydrochloric acid, sp. gr. 1.16, or 320 grains of bicarbonate, and 160 grains of tartaric acid, and the whole is kneaded and placed in the oven. When the mixture is made, the acid acts on the bicarbonate of soda, forming common salt, which is left in the dough, and carbonic acid is liberated at every point, and communicates a spongy texture to the mass. This process is chiefly used in making whole-meal bread, as the usual fermentation process would cause too much change in the bran, and produce a bread liable to sour by secondary fermentation. It is also employed in making 'fancy' and 'small bread.' Sesquicarbonate of ammonia is employed to some extent in the preparation of rusks, ginger-bread, and other light fancy bread; when heated, it entirely passes into gas, and thus yields a very spongy mass. Short-bread is prepared from flour with which butter has been incorporated.

Brown, Composition, or Whole-flour Bread is made from the ground but undressed wheat, and therefore contains the bran as well as the flour. Some years ago it was suggested that as the bran contained more nitrogenous matter than the flour, the whole meal must be more nutritious than the finer flour alone. But that opinion is now considerably modified. The great argument in favour of the use of whole-meal bread is that it contains more nitrogen than white bread. This is perfectly true, but as was pointed out by Wigner, the nitrogen of cereals exists in two forms—viz. the coagulable and the non-coagulable albuminoids, the former being those available for the purposes of nutrition, whilst the latter are almost useless for the purposes of food, consisting of alkaloids and salts of nitrogen. The fine portion of the flour was found by him to contain the nitrogen in the first condition, whilst the bran contained the comparatively useless form of nitrogen. A strong argument against the use of whole-meal bread is that the gritty particles which are present in the bran cause an unnatural irritation in the alimentary canal, and lead to a quicker evacuation of the but partially digested and absorbed food. This explains why brown bread possesses laxative properties, and why labourers fed on it consider that it makes them hungry soon again; they feel that it does not last in the stomach, and consequently think it has little nourishment in it.

The Act of 1836 prescribes that bread, except French rolls and fancy bread, must be sold by weight only; and the Factory and Workshops Act of 1878 regulates the condition of bakehouses. See also BISCUIT, CEREALIA, COOKERY, DIET, DIGESTION, FOOD, MILL, WHEAT.

AERATED BREAD is prepared by a process patented by Dr Dauglish in March 1859, and was at one time very popular, but its use is now almost exclusively confined to London and district. The process consists in placing the flour in a strong inclosed iron box, and moistening it with carbonic acid water, prepared as stated under Aerated Waters (q.v.). The dough is then worked up by machinery for ten minutes or so inside the box, from which it is dropped into moulds, which form it into loaves. It is then placed in an oven, when the carbonic acid, previously introduced with the water within the dough, expands, and forms a light palatable bread. The advantages claimed for this method of working bread are: (1) There is a saving of the whole of the waste caused by fermentation, which admits of more bread being made out of a sack of flour than by the old process; (2) The process, instead of occupying eight or ten hours, is completed in half an hour; (3) The cost of machinery and gas is less than that of yeast used in the old process; (4) The dough requires no handling to knead it and form it into loaves; (5) The bread is absolutely pure—it is simply flour, water, and salt. Not having undergone the process of fermentation, however, it has not the peculiar sweet flavour that we are accustomed to in ordinary bread, and the palate soon tires of the somewhat vapid taste.

GLUTEN BREAD is a bread prepared in such a way that it contains no starch or sugar, so as to be suitable as a food for diabetic patients. The flour is made into a stiff dough with water, and allowed to stand for a short time, usually an hour. It is then kneaded under running water so as to separate and wash away the starch. When the wash water ceases to be milky, the remaining gluten is made up into small rolls and baked.

The adulterations of bread are dealt with in the article on ADULTERATION.