BREAD, the name given to the staple food-product prepared by the baking of flour. The word itself, O. Eng. bréad, is common in various forms to many Teutonic languages; cf. Ger. Brot, Dutch, brood, and Swed. and Dan. bröt; it has been derived from the root of "brew," but more probably is connected with the root of "break," for its early uses are confined to "broken pieces, or bits" of bread, the Lat. frustum, and it was not till the 12th century that it took the place, as the generic name of bread, of hlaf, "loaf," which appears to be the oldest Teutonic name, cf. Old High Ger. hleib, and modern Ger. Laib.
History. - Bread-baking, or at any rate the preparation of cakes from flour or parched grain by means of heat, is one of the most ancient of human arts. At Wangen and Robenhausen have been found the calcined remains of cakes made from coarsely-ground grain in Swiss lake-dwellings that date back to the Stone Age. The cakes were made of different kinds of grain, barley and one-grained wheat (Triticum monococcum) being among the ingredients. This bread was made, not from fine meal, but from grain crushed between some hard surfaces, and in these lake-dwellings many round-shaped stones have been found, which were evidently used for pounding or crushing grain against the surface, more or less concave, of another stone (see Flour and Flour Manufacture). Perhaps the earliest form of bread, if that word may be used, was prepared from acorns and beech nuts. To this day a sort of cake prepared from crushed acorns is eaten by the Indians of the Pacific slopes. The flour extracted from acorns is bitter and unfit to eat till it has been thoroughly soaked in boiling water. The saturated flour is squeezed into a kind of cake and dried in the Sun. Pliny speaks of a similar crude process in connexion with wheat; the grain was evidently pounded, and the crushed remnant, soaked into a sort of pulp, then made into a cake and dried in the Sun. Virgil (Georgics, i. 267) refers to the husbandman first torrefying and then crushing his grain between stones: - "Nunc torrete igni fruges, nunc frangite saxo."
The question naturally arises, how did the lake-dwellers bake their cakes of bruised grain? Probably the dough was laid on a flat or convex-shaped stone, which was heated, while the cake was covered with hot ashes. Stones have been found among prehistoric remains which were apparently used for this purpose. In ancient Egyptian tombs cakes of durra have been found, of concave shape, suggesting the use of such baking-slabs; here the cake was evidently prepared from coarsely-cracked grain. In primitive times milling and baking were twin arts. The housewife, and the daughters or handmaids, crushed or ground the grain and prepared the bread or cakes. When Abraham entertained the angels unawares (Genesis xviii.) he bade his wife Sarah "make ready quickly three measures of fine meal, knead it, and make cakes upon the hearth." Professor Maspero says that an oven for baking bread was to be found in the courtyard of every house in Chaldaea; close by were kept the grinding stones. That bread prepared by means of leaven was known in the days of the patriarchs may be fairly inferred from the passage in Genesis ML, where it is said of Lot that he "made a feast, and did bake unleavened bread." Whether the shew-bread of the Jewish tabernacle was leavened is an open question, but it is significant that the Passover cakes eaten by Jews to-day, known as Matzos, are innocent of leaven. Made from flour and water only, they are about 12 in. in diameter, and have somewhat the look of water biscuits.
The ancient Egyptians carried the art of baking to high perfection. Herodotus remarks of them, "dough they knead with their feet, but clay with their hands." The practice of using the feet for dough kneading, however repulsive, long persisted in Scotland, if indeed it is yet defunct. The Egyptians used for their bread, wheat, spelt, barley and durra (sorghum). In the opinion of Dr Wallis Budge, barley was in Egypt the grain of most primitive culture. However that may be, it is certain that even in ancient Egypt white bread made from wheat was used by the rich. The form of the bread is revealed by ancient monuments. A common shape was a small, round loaf, something like the muffin of to-day. Other loaves were elongated rolls, and curiously enough were sprinkled on the top with seeds like modern Vienna bread.
The history of baking in classical Greece and Italy can be clearly traced. Athenaeus in his Deipnosophists minutely describes many different kinds of bread, which may be assumed to have been currently used in Greece. According to Pliny (Nat. Hist, xviii. II. § 28) Rome had no public bakers till after the war with Perseus (171-168 B.C.). That long after public bakehouses came into use the Romans and other urban dwellers in Italy continued to make a great deal of bread at home is certain. In Pompeii several private houses had their own mill and bakehouse. That city must also have possessed bakers by trade, as loaves of bread have been found, round in form, and stamped with the maker's name, possibly to fix responsibility for weight and purity. In the time of the Republic, public bakehouses were under the control of the aediles. Grain was delivered to the public granaries by the Saccarii, while another body called Catabolenses distributed the grain to the bakers. The latter were known as Pistores or "pounders," a reminiscence no doubt of the primitive time when grain was pounded by a pestle in a mortar. Slaves were largely employed in the irksome work of grinding, and when Constantine abolished slavery the staff of the pistrinae was largely recruited from criminals. The emperor Trajan incorporated about A.D. 100 the college of Pistores (millers and bakers), but its members were employers, not operatives. The work of a bakery is depicted in a set of bas-reliefs on the tomb of a master Pistor named Eurysaces, who flourished about a century before the foundation of the college. Here the grain is being brought and paid for; mills driven by horse and ass (or mule) power are busy; men are sieving out the bran from the flour by hand (bolters); bakers are moulding loaves on a board; an oven of domelike shape is being charged by means of a shovel (peel); and baskets of bread are being weighed on the one hand and carried off on men's backs on the other.
Regulation of Sale. - In the middle ages bakers were subjected to special regulations in all European lands. These regulations were supposed to be conceived in the interests of bread consumers, and no doubt were intended to secure fair dealing on the part of bread vendors. The legislators appear, however, to have been unduly biased against the baker, who was often beset by harassing restrictions. Bakers were formed into gilds, which were under the control, not only of their own officials, but of the municipality. In London the bakers formed a brotherhood as early as 1155, and were incorporated in 1307. There were two distinct corporate bodies concerned with bread-making, the Company of White Bakers and the Company of Brown Bakers; these were nominally united in 1509, but the union did not become complete till the middle of the 17th century. In Austria, bakers who offended against police regulations respecting the sale of bread were liable, until comparatively recent times, to fine, imprisonment and even corporal punishment. In Turkey the lot of the baker was very hard. Baron de Tott, writing of Constantinople in the 18th century, says that it was usual, when bread went to famine prices, to hang a baker or two. He would have us believe that it was the custom of master bakers to keep a second hand, who, in consideration of a small increase of his weekly wage, was willing to appear before the cadi in case a victim were wanted. A barbarous punishment, inflicted in Turkey and in Egypt on bakers who sold light or adulterated bread, consisted in nailing the culprit by his ear to the door-post of his shop. In France a decree of 1863 relieved bakers from many of the restrictions under which they previously suffered, but it did not touch the powers of the municipalities to regulate the quality and sale of bread. It left them the right conferred in 1791, to enforce the taxe du pain, the object of which was to prevent bakers from increasing the price of bread beyond a point justified by the price of the raw materials; but the right was exercised on their own responsibility, subject to appeal to higher authorities, and by a circular issued in 1863 they were invited to abolish this taxe officielle. In places where it exists it is fixed every week or fortnight, according to the average price of grain in the local markets.
In England an act of parliament was passed in 1266 for regulating the price of bread by a public assize, and that system continued in operation till 1822 in the case of the city of London, and till 1836 for the rest of the country. The price of bread was determined by adding a certain sum to the price of every quarter of flour, to cover the baker's expenses and profit; and for the sum so arrived at tradesmen were required to bake and sell eighty quartern loaves or a like proportion of other sizes, which it was reckoned each quarter of flour ought to yield. The acts now regulating the manufacture and sale of bread in Great Britain are one of 1822 (Sale of Bread in the City of London and within 10 m. of the Royal Exchange), and the Bread Act of 1836, as to sale of bread beyond 10 m. of the Royal Exchange. The acts require that bread shall be sold by weight, and in no other manner, under a penalty not exceeding forty shillings. This does not, however, mean that a seller is bound to sell at any particular weight; the words quartern and half-quartern, though commonly used and taken to indicate a 4-lb and 2-lb loaf respectively, have no legal sanction. That is to say, a baker is not bound to sell a loaf weighing either 4 lb or 2; all he has to do, when a customer asks for a loaf, is to put one on the scale, weigh it, and declare the weight. When bread is sold over the counter it is usual for the vendor to cut off and tender a piece of bread to make up any deficiency in the loaf. This is known as the "overweight." There is little doubt the somewhat misty wording of the bread acts lends itself to a good deal of fraudulent dealing. For instance, when bread is sold over the counter, two loaves may be 5 or 6 oz. short, while the piece of makeweight may not reach an ounce. The customer sees the bread put on the scale, but in ninety-nine cases out of a hundred does not trouble to verify the weight, and unless he expressly asks for 2 lb or some specific weight of bread, it is very doubtful whether the seller, having satisfied the letter of the law by placing the bread on the scales, could be convicted of fraud. The provision as to selling by weight does not apply to fancy bread and rolls. No exact definition of "fancy bread" has ever been laid down, and it must be largely a question of fact in each particular case. All bakers or sellers of bread must use avoirdupois weight, and must provide, in a conspicuous place in the shop, beams, scales and weights, in order that all bread there sold may from time to time be weighed in the presence of the purchaser. The penalty for using any other weight than avoirdupois is a sum not exceeding £5 nor less than forty shillings, and for failing to provide beams and scales a sum not exceeding £5. Also every baker and seller of bread, delivering by cart or other conveyance, must be provided with scales and weights for weighing bread; but since the Weights and Measures Act 1889, no penalty is incurred by omission to weigh, unless there has been a request on the part of the purchaser. The acts also define precisely what ingredients may be employed in the manufacture of bread, and impose a penalty not exceeding £10 nor less than £5 for the adulteration of bread. (See further under Adulteration.)
Although the act of 1836 extends to the whole of the United Kingdom (Ireland excepted) out of the city of London and beyond 10 m. of the Royal Exchange, yet in many Scottish burghs this act is replaced by local acts on the sale of bread. These are in all cases of a much more stringent nature, requiring all batch or household bread to be stamped with the reputed weight. Any deficiency within a certain time from the withdrawal of the bread from the oven is an offence. The London County Council desired to introduce a similar system into the area under their jurisdiction, and promoted a bill to that effect in 1905, but it fell through. The bill was opposed not only by the National Association of Master Bakers, the London Master Bakers' Protection Society, and by the West End metropolitan bakers in a body, but also by the Home Office, which objected to what it termed exceptional legislation.
It may be noted that the acts of 1822 and 1836 define precisely what may and may not be sold as bread. It is laid down in section 2 that "it shall and may be lawful ... to make and sell ... bread made of flour or meal of wheat, barley, rye, oats, buckwheat, Indian corn, peas, beans, rice or potatoes, or any of them, and with any (common) salt, pure water, eggs, milk, barm, leaven, potato or other yeast, and mixed in such proportions as they shall think fit, and with no other ingredients or matter whatsoever."
Sanitation of Bakehouses. - The sanitary arrangements of bakehouses in England were first regulated by the Bakehouse Regulation Act 1863, which was repealed and replaced by the Factory and Workshop Act 1878; this act, with various amending acts, was in turn repealed and replaced by the Factory and Workshop Act 1901. By the act of 1901 a bakehouse is defined as a place in which are baked bread, biscuits or confectionery, from the baking or selling of which a profit is derived. The act of 1863 placed the sanitary supervision of bakehouses in the hands of local authorities; from 1878 to 1883 supervision was in the hands of inspectors of factories, but in 1883 the supervision of retail bakehouses was placed in the hands of local authorities. Under the act of 1901 the supervision of bakehouses which are "workshops" is carried out by local authorities, and for the purposes of the act every bakehouse is a workshop unless within it, or its close or curtilage or precincts, steam, water or other mechanical power is used in aid of the manufacturing process carried on there, in which case it is treated as a non-textile factory, and is under the supervision of factory inspectors.
The more important regulations laid down by the act are: (1) No water-closet, etc., must be within or communicate directly with the bakehouse; every cistern for supplying water to the bakehouse must be separate and distinct from any cistern supplying a water-closet; no drain or pipe for carrying off sewage matter shall have an opening within the bakehouse. (2) The interior of all bakehouses must be limewashed, painted or varnished at stated periods. (3) No place on the same level with a bakehouse or forming part of the same building may be used as a sleeping place, unless specially constructed to meet the requirements of the act. (4) No underground bakehouse (one of which the floor is more than 3 ft. below the surface of the footway of the adjoining street) shall be used unless certified by the district council as suitable for the purpose (see Redgrave, Factory Acts; Evans Austin, Factory Acts).
Bread Sluffs. - As compared with wheat-flour, all other materials used for making bread are of secondary importance. Rye bread is largely consumed in some of the northern parts of Europe, and cakes of maize meal are eaten in the United States. In southern Europe the meal of various species of millet is used, and in India and China durra and other cereal grains are baked for food. Of non-cereal flour, the principal used for bread-making is buckwheat (Fagopyrum esculentum), extensively employed in Russia, Holland and the United States. The flour of pease, beans and other leguminous seeds is also baked into cakes, and in South America the meal of the tapioca plant, Jatropha Manihot, is employed. But, excepting rye, none of these substances is used for making vesiculated or fermented bread.
Quality of flour
A normal sample of wheat-flour consists roughly of 10 parts of moisture, 72 of starch, 14 of nitrogenous matter, 2.25 of fatty matters, and 1.75% of mineral matter. Starch is thus the predominating component; it is not, however, the dough-forming ingredient. By itself, starch, when saturated with water, forms a putty-like mass devoid of coherence, and it is the gluten of the nitrogenous matter which is the binding constituent in dough-making, because when wetted it forms a more or less elastic body. The proportion of gluten in wheat-flour varies from 7 to 15%, but the mere quantity of gluten is by no means the only standard of the commercial value of the flour, the quality also counting for much. One of the functions of gluten is to produce a high or well-piled loaf, and its value for this purpose depends largely on its quality. This is turn depends largely on the variety of wheat; certain races of wheat are much richer in nitrogenous elements than others, but such wheats usually only flourish in certain countries. Soil and climate are undoubtedly factors in modifying the character of wheat, and necessarily therefore of the flour. The same wheat grown in the same soil will show very varying degrees of strength (i.e. of gluten) in different seasons. For instance, the north-western districts of America grow a hard spring wheat which in a normal season is of almost unequalled strength. In 1904 an excess of moisture and deficiency in Sun in the Red River Valley during the critical months of June and July caused a serious attack of red and black rust in these wheat fields, the disease being more virulent in the American than the Canadian side of the valley. The result was that the quality of the gluten of that season's American spring wheat was most seriously affected, its famed strength being almost gone. Wheat from the Canadian side was also affected, but not nearly to so great an extent. Flour milled from hard winter wheat in the American winter districts is sometimes nearly as strong as the spring wheat of the North-west. Hungarian flour milled from Theis wheat is also very strong, and so is the flour milled from some south Russian spring wheats. But here again the degree of strength will vary from season to season in a remarkable manner. In the main each land has its own clearly marked type of wheat. While the United States, Canada, Hungary and Russia are each capable of growing strong wheat, Great Britain, France and Germany produce wheat more or less weak. It follows that the bread baked from flour milled from wheat from British, French or German wheat alone would not make a loaf of sufficient volume, judged by present British standards. As a matter of fact, except in some country districts, British bakers either use strong foreign flour to blend with English country flour, or, more frequently, they are supplied with flour by British millers milled from a blend in which very often English wheat has a small, or no place at all. If the baker's trade calls for the making of household bread, especially of the London type, he must use a strong flour, with plenty of staple gluten in it, because it is this element which supplies the driving or lifting force, without which a high, bold loaf cannot be produced. If the demand is for tin or (as it is called in many parts of the north of England) pan bread, a weaker flour will suffice, as the tin will keep it up. A Vienna loaf should be made with at least a certain proportion of Hungarian patent flour, which is normally the highest-priced flour in the market, though probably the bulk of the Vienna rolls made in London contain no Hungarian flour. A cake of flat shape can be very well made with a rather weak flour, but any cake that is required to present a domed top cannot be prepared without a flour of some strength.
Flavour of flour
It is a general opinion, though contested by some authorities, that soft, weak flours contain more flavour than strong, harsh flours. The strong wheats of the American and Canadian North-West make less flavoury flour than soft red winter from the American South-West. It would not, however, be correct to say that all strong wheats are necessarily less full of flavour than weak wheats. Hungarian wheat, for instance, is one of the strongest wheats of the world, but has a characteristic and pleasant flavour of its own. Indian wheats, on the other hand, are not particularly strong, but are liable to give a rather harsh flavour to the bread. English, French and German wheats, when harvested in good condition, produce flour of more or less agreeable flavour. None of these wheats could be classified as strong, though from each of those lands wheat of fair strength may be obtained under favourable meteorological conditions. The Australasian continent raises white wheat of fine quality which has much affinity with British wheat - it is the descendant in many cases of seed wheats imported from England - but it is occasionally stronger. The resultant flour is noted for its sweetness. Both millers and bakers who are concerned with the supply of high-class bread and flour make free use of what may be termed flavoury wheats. The proportion of English wheat used in London mills is very small, but millers who supply West-End bakeries with what is known as top-price flour are careful to use a certain amount of English wheat, if it is to be had in prime condition. They term this ingredient of their mixture "sugar." London bakers again, with customers who appreciate nicely flavoured bread, will "pitch" into their trough a certain proportion of English country flour, that is, flour milled entirely or chiefly from English wheat, which under such conditions is strengthened by a blend of strong flour, a patent flour for choice. It has been objected that as English wheat contains a large proportion of starch, and as starch is admittedly destitute of flavour, there is no reason why flour milled from English wheat should possess a sweeter flavour than any other starchy wheat flour. Experience, however, has amply proved that well-ripened English wheat produces bread with an agreeable flavour, though it does not follow that all English wheat is under all conditions capable of baking bread of the highest quality. But it would be as fallacious to hold that weak flour is necessarily flavoury, as that all strong flour is insipid and harsh. Different wheats are undoubtedly possessed of different flavours, but not all these flavours are of a pleasing character. In some cases the very reverse is true. Californian and Australian wheats have occasionally aromatic odours, due to the presence of certain seeds, that will impart an objectionable flavour to the resultant bread.
While the essential character of particular wheats will account for a good deal of the flavour that may be detected in the bread made from them, the baking process must also be responsible to some extent for flavour. The temperature of the oven and the degree of fermentation must be factors in the question. It has been asserted that the same flour will bake into bread of very different flavour according as the fermentation is carried out slowly or quickly, or as the oven is hot or the reverse. A high temperature seems to have the effect of quickly drawing out the subtle essences which go to give flavour to the bread, but it is a question whether they are not subsequently rapidly volatilized and partially or wholly lost. The rapid formation of a solid crust is no doubt likely to retain some of these flavouring essences. A moist, or "slack," sponge, or dough, appears distinctly favourable to the retention of flavour, the theory being that under such conditions the yeast, having more room to "breathe," works more easily, and is therefore less likely to convert into food those soluble constituents of the flour which give flavour.
Colour of flour
The colour of flour is a valuable, though not an infallible, index to its baking qualities. Thus, a flour of good colour, by which bakers mean a flour of bright appearance, white, but not a dull dead white, will usually bake into a loaf of good appearance. At the same time, a flour of pronounced white tint may bake into a dirty grey loaf. This has been particularly noted in the case of flours milled in Argentina. The colour of flour will vary from a rich, creamy white to a dull grey, according to its quality. The different shades are many and various, but the prevailing tints are comparatively few. Perhaps Blandy's classification of the colours as white, yellow, red, brown and grey is as serviceable as any. Each of these tints is directly caused by the presence of certain substances. White denotes the presence of a considerable proportion of starch, while a pronounced yellow tint proclaims gluten of more or less good quality. Red and brown are tints only found in flours of low grade, because they are sure proofs of an undue proportion of branny or fibrous particles. A greyish flour invariably contains impurities, such as crease dirt, from the wheat, the intensity of the tint varying in proportion to their amount. With regard to a yellow tint, though this always denotes the presence of gluten, it is difficult to estimate the baking quality of the flour by the shade of yellow. In the best Hungarian patent flour the whole sample will be suffused by an amber tint, known to Budapest and Vienna bakers as gelblicher Stich. Rolls baked from the best Hungarian flour will not infrequently cut yellow as if eggs had been used in making them up, though nothing more than flour, yeast and water has been employed. Strong flour milled from American or Canadian spring wheat is also yellowish in colour, but the tint is not so deep as with Hungarian flour. On the other hand, there are flours of no great strength, such as those from some Australian wheats, which are apt to look yellow. When the colour of flour is not maintained in the bread, the reason is generally to be found in the baking process employed. Colour is a fairly trustworthy, but not an absolute guide to the chemical composition of flour.
Damp and flour
Unfortunately not all flour of good colour is sound for bread-making purposes. Wheat which has been harvested in a damp condition, or has been thoroughly soaked, by drenching showers previous to cutting, or has got wet in the stook, is liable, unless carefully handled, to produce flour that will only bake flat, sodden loaves. Wheat which has received too much rain as it is approaching maturity, and has then been exposed to strong sunlight, is peculiarly liable to sprout. This seems to happen not infrequently to La Plata wheat, and though wheat shippers in that country are usually careful to clean off the little green spikes, this outward cleansing does not remedy the mischief wrought to the internal constitution of the berry. Such wheat makes flour lacking in strength and stability. Its gluten is immature and low in percentage, while the soluble albuminoids are in high percentage and in a more or less active diastasic state. The starch granules are liable to have weakened or fissured walls, and the proportion of moisture and of soluble extract will be high. With regard to the beneficial action of kiln or other drying on damp flour, William Jago was convinced by a series of experiments that the gentle artificial drying of flour increases its water-absorbing capacity to about three times the amount of water lost by evaporation. On the other hand, a damp flour dried too quickly and at too great a heat is liable to be made more instead of less susceptible to diastasic changes.
Alum. - Strictly speaking, when employed with weak and unstable flours alum is a remedial agent. The popular idea that it acts as a kind of bleacher of flour, having the faculty of converting flour that is dark-coloured through containing a sensible proportion of branny particles and woody fibre, into white-coloured loaves, is erroneous. Its action as a producer of white bread is indirect, not direct, though it is none the less effective. It seems to act as a brace to or steadier of unstable gluten. If from the same wheat a certain proportion of gluten be extracted and divided into two parts, of which one is placed in a glass of water containing a strong solution of alum, and the other in a glass of plain water, the gluten in the latter case will become spent days and perhaps weeks before the sample in the alumed water is disintegrated. The place of alum in the process of fermentation is well marked. By holding together unstable gluten, it checks the diastasic action, and the proportion of starch converted into glucose (grape sugar) is reduced, with the result that a whiter and more porous loaf is produced. It is generally admitted that by the use of alum more or less eatable bread may be baked from flour which otherwise could hardly be made into bread at all. Strictly, therefore, this substance is not an adulterant, inasmuch as it is not a substitute in any sense for flour. But it is admittedly unwholesome, and therefore its legal interdiction for alimentary purposes is quite justifiable. Another aspect of the use of alum is that it is employed for the purpose of enabling bakers to use poor flour.
A fairly satisfactory test for alum in bread (or flour) is afforded by an alkaline solution of logwood and a saturated solution of ammonium carbonate. The presence of alum is shown by a lavender or full blue colour. The depth of the tint is said to be a rough guide to the quantity of alum present. According to Jago this test is so sensitive that it has resulted in the detection of 7 grains of alum in a 4-lb loaf.
Besides alum, small quantities of copper sulphate have been used for checking diastasis and retarding fermentation. This substance has the same effect as alum, but as all copper salts are active poisons, the employment of copper sulphate is most strongly to be condemned.
Lime-water. - The object of using either alum or copper sulphate is to check over-rapid diastasis during fermentation. Baron Liebig pointed out a much less objectionable means of attaining the same end by means of lime-water, about 1 oz. of fresh quicklime being dissolved in the water used for doughing one sack of flour. Bread made in this way is said to be spongy in texture, of agreeable flavour, and perfectly free from acidity. In the baked loaf the lime is transformed into calcium carbonate (chalk) by the carbon dioxide resulting from the panary fermentation. It is said that an increased yield of bread may be obtained by the use of lime-water; the explanation may be that lime-water, by retarding the degradation of the gluten and the diastasis of the starch, increases the water-retaining power of the flour, so that the same weight of flour yields a greater volume of bread.
Unvesiculated and Vesiculated Bread. - Wheaten bread may be divided into two main divisions, unvesiculated and vesiculated. The term vesiculated simply means provided with vesicles, or small membranous cavities, such as are found in all bread that has been treated by yeast, leaven or any other agent for rendering it spongiform in structure by the action of carbonic acid gas. Nearly all bread eaten by civilized folk is vesiculated, though there are different methods and processes for attaining this result. Into the category of unvesiculated bread enter such products as the Australian damper, a flat cake prepared from flour, water and salt, and baked in the hot ashes of a wood fire. The dough is spread on a flat stone and covered with a tin plate, while the hot ashes are heaped around and over it; the heat should not be much in excess of 212° Fahr. The scone, the bannock and other similar cakes, still much appreciated in Scotland and the north of England, are also examples of unvesiculated bread. They are baked on hot plates or "griddles," on hearths, and sometimes in ovens. Biscuits differ from these cakes in the fact that they are baked by a high instead of a moderate heat. But they enter so far into the class of unvesiculated bread that they are generally prepared without the aid of any such aerating agent as carbon dioxide. (See Biscuit.)
Vesiculated bread is now the only article of diet made from flour to which the term bread is applied, and there are various ways of producing the spongiform texture by which it is characterized. The ordinary and doubtless the most satisfactory way is by developing the carbon dioxide within the dough itself by the use of yeast (q.v.) or leaven, which sets up alcoholic fermentation, splitting up the saccharine matters in the flour into alcohol and carbon dioxide. The latter is retained by the dough and distends it, causing the bread to "rise." Or the carbon dioxide may be artificially introduced, as in the so-called "aerated" bread (see below), or it may be produced by the agency of certain chemicals, as for instance of baking powders.
Such powders are mixtures which, under the influence of either water or heat, evolve carbon dioxide. These powders have been divided by Jago into three groups: - (1) Tartrate powders, in which the acid constituent is either free or partly combined tartaric acid; (2) Phosphate powders, in which the acid is some form of phosphoric acid; (3) Alum powders. All these powders have a more or less aperient action on the human system. Tartrate powders have the disadvantage that both commercial tartaric acid and cream of tartar frequently contain lead, a poisonous substance. Phosphate powders are less open to objection, as they are more easy to obtain free from lead and other metallic impurities. Alum powders contain potassium bisulphate and alum. It is somewhat remarkable that while the presence of alum in bread is regarded by the law of England as adulteration, its use in baking powder was pronounced legal in James v. Jones, 1894, 1, Q.B. 304, on the ground that baking powder is not food within the meaning of the Sale of Food and Drugs Act 1875. In making wholemeal bread, hydrochloric acid and sodium bicarbonate are often used in such proportions that they neutralize each other. Carbon dioxide is evolved and raises the dough. In preparing wholemeal bread the use of this combination has the advantage that the acid acting rapidly on the sodium bicarbonate soon produces enough carbon dioxide to aerate the dough, and thus hasten its entry into the oven. Wholemeal flour contains so large a proportion of cerealin that diastasis is apt to proceed rapidly, the result being a clammy, sodden loaf. For this reason, perhaps the so-called aerated process is even more suitable for making wholemeal than white bread.
Methods of dough-making differ in different countries, and even in different parts of the same land. In the off hand method the dough is made right off, without any preliminary stages of ferment or sponge. This plan is sometimes adopted for making tin bread, and occasionally for crusty loaves. For tin bread a strong flour would be used and made into a slack dough, and about 1 lb to 2 lb of distillers' yeast would be used for the sack (280 lb) of flour, occasionally with the addition of a little brewers' yeast. Salt is used in the proportion of 3 lb to 3 lb per sack. Formerly also it was the custom to add 10-14 lb of boiled potatoes, but the use of potatoes has greatly decreased. A tin-bread dough would be made slack, with about 70 quarts of water to the sack, and after being mixed, would be fermented at a temperature of 76-80° Fahr. It should lie for about ten hours. A dough for crusty bread such as cottage loaves, would be made much tighter, not more than 60 quarts of water being allowed to the sack. It would be fermented at a higher temperature, and would not lie more than about six hours. A slack dough is much less laborious to work (when the dough is hand-made) than a tight dough, for which a mechanical kneader is very suitable, but as a matter of fact the use of machinery (see below) is still the exception, not the rule. When a stiff dough is made by hand, it is usually made somewhat slack to begin with, and then "cut back" and "dusted" at regular intervals, that is to say, more and more flour is added till a dough of the required consistency has been obtained. (In the British baker's vocabulary "dust" means flour, and good dust stands for good flour.) This system, on the one hand, saves the labour involved for "sponging" and other operations, and the bread is produced in less time; but on the other hand more yeast is used, and bakers generally hold that the system sacrifices the colour and texture of the loaf to convenience of working and yield. The high porportion of yeast enables the dough to carry a large quantity of water, and about 104 4-lb loaves to the sack is said by Jago to be a not unusual yield in the case of slack doughs. But such a result would only be possible with very strong flour. In an ordinary way 96 loaves to the sack is a very high yield, unattainable except with strong flour, and probably the average yield is not more than 90 loaves to the sack. In London the manager of a "tied" shop is usually held to account for 92 loaves to the sack.
In the ferment and dough system, the ferment usually consists of 10 to 14 lb of potatoes to the sack of flour, boiled or steamed, and mashed with water, so as to yield about 3 gallons of liquor. There are several substitutes for potatoes, including raw and scalded flour, malt, malt extracts, etc.; brewers' or distillers' yeast may also be used. A ferment should contain saccharine matters and yeast stimulants in such a form as to favour the growth and reproduction of yeast in a vigorous condition. Hence it should not be too concentrated. About six hours are required for its preparation. It is added, together with 2 to 3 lb of salt, to the dough, which is prepared with about 56 quarts of water to the sack, and worked at a temperature of 80-84° Fahr. The dough is allowed to lie from two to five hours according to the flour used, the character of the ferment, and the working temperature. In this system the proportion of strong flour is usually reduced to 40% of the dough, and no doubt in some cases only soft or weak flours are used. Naturally the yield of bread is not so high as in the case of an off hand dough made entirely from strong flour, and it will probably not exceed 90 loaves to the sack. This method has many advantages. After the ferment is made the labour required is not much greater than with the off hand doughs, and less yeast is required, while potatoes, which are somewhat troublesome, from the necessary cleaning, can be replaced by the substitutes already mentioned. The method produces good-looking and palatable bread, though the loaves should be eaten within some twelve hours of leaving the oven.
The sponge and dough system, which is probably in widest use in England, is adapted to almost every kind of bread, and has the advantage that any kind of flour can be employed. The stronger flours which need long fermentation can be and usually are used in the "sponge" stage, while soft flours are utilized in the dough. (The sponge is a certain proportion, varying from a quarter to one-half, of the flour necessary for making the batch.) In London the baker often uses for the sponge a bag (140 lb) of American spring wheat flour, and for the dough a sack (280 lb) of British milled flour, which, whether it be country flour milled largely from English wheat or London milled, is always softer and weaker than that used for the sponge. The sponge is made very slack, 26 to 32 quarts of water being used to say 100 lb of flour. Yeast, either distillers' or brewers', must be added, in proportions varying according to its character and strength. Of distillers' yeast 6 to 10 oz. may be used for 280 lb of flour (including sponge and dough). Salt is added to the sponge sparingly, at the rate of about lb to the sack of 280 lb The object of making the sponge so slack is to quicken the fermentation. When set the sponge is allowed to ferment from six to ten hours, according to temperature and other conditions. Sometimes all the water it is intended to use is put into the sponge, which is then known as a "batter" sponge. The sponge, when ready, is incorporated with the rest of the flour to which the necessary amount of water and salt is added. The whole mass is then doughed up into the requisite consistency, the dough being allowed to lie for about two hours. Bread made by this method, always assuming that over-fermentation has been avoided, is of good appearance, presenting a bold loaf, with even texture and a nice sheen. Owing to the use of soft flours, the flavour should be agreeable, and the loaves ought to keep much longer than bread made by ferment and dough. The yield may rise as high as 96 loaves per sack, if strong flour has been used in the sponge.
A combination of the above two methods, known as the ferment, sponge and dough system, is often used with brewers' yeast. In this case the yeast is not added to the sponge direct, but goes into the ferment. This method is rather in favour with bakers who make their own yeast.
The system of bread-making generally used in Scotland is known as the flour barm, sponge and dough. The barm is a combination of a malt and hop yeast, with a slow, scalded flour ferment. To make the so-called "virgin" barm a Scottish baker would use a 30-gallon tub; a smaller vessel for malt-mashing; 10 lb malt; 3 oz. hops and a jar for infusing them; 40 lb flour; 2 to 3 oz. malt; 8 to 12 oz. sugar, and 18 gallons of boiling water. With these materials a powerful ferment is produced, which it is considered best to use in the sponge the fourth or fifth day after brewing. The sponges used in Scotland are "half" or "quarter." About 6 lb of malt go to the sack, one-sixth going into the sponge. As in England, strong flours are used for the sponge, but rather stronger flours are used for the dough than is usual in England. Scottish loaves are largely of the "brick" type, high and narrow. Such bread has an attractive appearance and keeps well. It has a rather sharp flavour, approaching acidity but avoiding sourness, while the large quantity of malt used adds a characteristic taste. The yield rises in some Glasgow bread factories to 100 loaves to the sack.
In many parts of Europe bread is still made from leaven, which, properly speaking, consists of a portion of dough held over from the previous baking. This substance, known to French bakers as levain, is called in Germany Sauerteig (anglice "sour dough"). The lump of old dough, placed aside in a uniform temperature for some eight hours, swells and acquires an alcoholic odour, becoming the levain de chef of the French bakers. It is then worked up with flour and water to a firm paste double its original volume, when it becomes the levain de première. Six hours later, by the addition of more flour and water its amount is again doubled, though its consistency is made rather softer, and it becomes the levain de seconde. Finally, by another addition of flour and water, the amount is again doubled, and the levain de tous points is obtained. This mass is divided into two parts; one is baked yielding rather dark sour bread, while the other is mixed with more flour and water. This second portion is in turn halved, part is baked, and part again mixed with more flour, this last batch yielding the best and whitest bread. In North Germany leaven is generally used for making rye bread, and loaves baked from a mixture of wheat and rye flour. In the bakery of the Krupp works at Essen, each batch of the so-called Paderborn bread is prepared entirely with leaven from 270 kilos of rye flour (patent quality), 100 of wheat flour (seconds), 2 of buckwheat meal, 6 of salt, 5 of leaven, and one litre of oil. In Vienna leaven is never used for making the rolls and small goods for which that city is famous. Viennese bakers use either brewers' yeast or a ferment, prepared by themselves, of which the basis is an infusion of hops. Brewers' yeast is added to the ferment, which takes the form of a very slack dough. With 100 kilos (220.46 lb) of flour about 17 litres or nearly 2 gallons of ferment are used.
In the original Dauglish process for the manufacture of aerated bread, which was brought into operation in Great Britain in 1859, carbonic acid gas was evolved in a generating vessel by the action of sulphuric acid on chalk, and after purification was forced at high pressure into water, which was then used for doughing the flour. In this process the flour that had to be made into bread was submitted to the action of the super-aerated water by direct transference. It was found, however, in practice that much difficulty occurred in making the gas admix readily with the flour and water, great pressure being required, and to lessen the difficulties a new process, called the "wine whey," was introduced. To carry this out, a vat placed on the upper storey of the factory is charged with a portion of malt and flour, which is mashed and allowed to ferment until a weak and slightly acid thin wine is produced; this after passing through the coolers is stored until it is transformed into a vinous whey. This whey is then introduced into a strong cylinder partly filled with water, and is aerated by letting in the gas (now stored in a highly compressed form in bottles), the pressure required being only a quarter of that necessary with the original method. The flour having been placed in the mixers, which are of globular form containing revolving arms, the aerated fluid is admitted, and in a short period the flour and fluid are completely incorporated. By means of an ingenious appliance termed a dough cock, the exact amount of dough for a single loaf of bread is forced out under the pressure of the gas, and by reversing the lever the dough, which expands as it falls into a baking tin, is cut off. Two sacks of flour can be converted with ease into 400 2-lb loaves in forty minutes, whereas the ordinary baker's process would require about ten hours. At first a difficulty was encountered in the fact that the dough became discoloured by the action of the "wine whey" on the iron, but it was overcome by Killingworth Hedges, who discovered a non-poisonous vitreous enamel for coating the interior of the mixers, etc. It has been claimed for the Dauglish process that it saves the baker risks attendant on the production of carbon dioxide by the ordinary process of fermentation, in that he is no longer liable to have his dough spoilt by variations of temperature and other incalculable factors, the results being certain and uniform. A further claim is the saving of the proportion of starch consumed by conversion into glucose during the process of fermentation. The original objection, that, by the absence of fermentation, those subtle changes which help to produce flavour are lost, is annulled by the use of the wine whey process. The Dauglish process is well suited for producing small goods, such as cakes and scones, where flavour can be artificially imparted by means of currants, flavouring essences, etc. An undoubted advantage of the aerating process of bread-making is adaptability for utilizing flour with unstable gluten, which can thus be made into an excellent quality of bread. For wholemeal bread, too, there is probably no more suitable process than the Dauglish. The strong diastasic action of the cerealin, inevitable in fermentation, is entirely avoided. The Aerated Bread Company have about a hundred depots in London, which are supplied from a central factory.
The essence of the bread-making process recently invented by Serge Apostolov is the combination of a flour mill and bakery. The wheat, after a preliminary cleaning, is ground into flour by a mill composed of metal disks dressed, that is furrowed, very much like the surfaces of a pair of mill-stones. The disks are not set to grind very close, because it is desired, by minimizing friction, to keep the meal cool. From the middlings obtained by this milling process about 10% of bran is separated, and the remainder of the middlings is treated by a peculiar process, akin to mashing, termed "lixiviation." The middlings are saturated with tepid water containing a small proportion of yeast, which causes a certain amount of fermentation. It is claimed that by this process a solution is obtained of the floury constituents of the middlings. From the vats the solution is poured on an inclined sieve which has a gentle reciprocating motion. The floury particles pass through the meshes, while the bran tails over the sieve; the proportion of the wheat berry thus rejected is given as about 2%. On the other hand, the milky-looking solution, called "lactus," is caught in a special vessel, and delivered by a shoot into a trough, which may be either a mechanical kneader of an ordinary trough. This lactus takes the place of the ordinary sponge. The flour is added in the proportion necessary to make the required batch and the whole mass is doughed, either by hand or power. The resultant dough is moulded in the ordinary way into loaves, which are baked in due course. The advantages claimed for the process are that it permits of the utilization in bread-making of about 87% of the wheat berry, that the resultant bread is fairly white in colour and is agreeable in flavour, and that it is extremely simple and provides a ready and cheap means of flour-making.
Machine Bakeries. - Bread-baking, though one of the most important of human industries, was long carried out in a most primitive manner, and machinery is still practically unknown in the bulk of British bakehouses. The reasons for this apparently anomalous condition of things are not very far to seek. Bread, unlike biscuits, is a food quite unfitted for long storage, and must be consumed within a comparatively short time of being drawn from the oven. Hence the bread-baker's output is necessarily limited to a greater or lesser degree. This will be the more apparent when it is considered that the cost of distributing bread is high relatively to the profits to be realized. A baker's bread trade is therefore usually limited to local requirements, and trading on a small scale he has less inducement to lay out capital on the installation of machinery than other classes of manufacturers. But there are now many machine bakeries (known in Scotland as bread factories), both in London and in other parts of Great Britain, where the manufacture of bread is carried out more or less on a large scale. The evolution of the machine bakery has been slow, and the mechanical operations of the bakehouse were long limited to the mixing of the sponge and the kneading of the dough, but now the work of the bakery engineer extends over almost every operation of bread-making.
A bread-baking plant should be installed in a building of at least two storeys. The ground floor may be used for the shop, with possibly a bread-cooling and delivery room at the rear. The flour may be hoisted to an attic at the top of the building, or to the top floor; in any case there must be sufficient floor space to accommodate the flour sacks and bags. Underneath the floor of the flour store should be installed a flour sifter, a simple apparatus consisting essentially of a hopper through which the flour enters a cylinder with a spiral brush, by which it is thoroughly agitated previously to passing through one or more sieves placed under the brush. A sack of flour may be passed through this sifter in a couple of minutes, the operation freeing the flour from lumps and pieces of string or other foreign substances which may have found their way into the sack. The sifter may also be combined with a blender or mixer, so that the baker may by its means thoroughly blend different flours in any desired proportion. The operation of blending is usually effected by a revolving blade of suitable design or by a worm conveyor placed underneath the sieve or sleeve. From the sifter and blender the flour descends by a sleeve into the dough kneading machine on the floor below. But in cases where it is desired merely to sift and blend flour ready for future use, it may be received in a worm and elevated again to the storage floor by an ordinary belt and bucket elevator. The water required for doughing purposes is contained in an iron tank, fixed to the wall in convenient proximity to the dough kneader. This tank, known as a water attemperating and measuring tank, is provided with a gauge and thermometer, and from it the exact quantity of water needed for doughing can be rapidly drawn off at the desired temperature. The cold water supply may be let into the tank at the top, and the hot water supply at the bottom, the idea being that each supply shall permeate the whole mass by gravity, the hot water ascending and the cold descending. The chief types of dough kneader will be described subsequently, but here it should be noted that not only have machines been devised for cutting out the exact sizes of dough required for small goods, such as buns and tartlets, but that the operations of weighing and dividing dough for quartern and half-quartern loaves can also be neatly and economically effected by machinery. Further, at least two machines have been built which successfully mould loaves (of simple shape), and the problem of moulding household bread by machinery has certainly been solved, but whether delicate twists and other fancy shapes could be equally well moulded mechanically is less certain.
The machine bakery, however complete, is not likely ever to be quite automatic and continuous like a modern flour mill, where the plant is connected throughout and virtually forms one machine (see Flour and Flour Manufacture), and though the engineer has at least managed to effect every operation of the bakehouse by mechanical means, it is not yet possible to shoot a sack of flour into the hopper of the sifter on the top floor, and to turn it into bread, without any human intervention whatever, though as things are, the moulded dough can be put into the oven without undergoing actual contact with human hands. In practice, some of the machines mentioned above are often dispensed with, even in so-called machine bakeries. The flour sifter and blender is indeed found in many bakeries where mechanical kneaders are unknown, while not in all machine bakeries would be found dough weighers and dividers, still less moulding machines. The economical side of the argument on behalf of machinery is presented in the familiar shape that a properly equipped machine bakery can turn out better work at a lower cost (by dispensing with labour), or at any rate can carry on a bigger trade with the same staff. There is plausibility in this argument, but it must be admitted that innumerable bakeries of capacities varying from 10 to 20 sacks per week are carried on more or less successfully without machinery of any kind, beyond perhaps a sifter or blender. Moreover, some of these bakehouses produce bread which can hardly be improved on.
One advantage claimed for flour sifters, besides removing the impurities, is that by thoroughly aerating flour they cause it to become more "lively," in which condition it kneads more readily. It is also quite possible that the air which is thus incorporated with the dough has a stimulating effect on the yeast, causing a more energetic fermentation. A strong argument in favour of dough kneaders is their hygienic aspect. It is agreed that the operation of dough stirring by hand, since it involves severe labour conducted in a heated atmosphere, must be liable to cause contamination of the dough through emanations from the bodies of the operatives. In well-managed bakeries the utmost personal cleanliness on the part of the staff is exacted, but the unpleasant contingency alluded to is certainly possible. It is also contended that the use of machinery for dough kneading and batter whisking will ensure better work, in the sense that the mass under treatment will be more thoroughly worked by mechanically driven arms of iron or steel than by human limbs, liable to weariness and fatigue. The better worked the dough, the greater its power of expansion, and consequently the greater its bread-making value.
The most widely known machine used in connexion with bread-baking, next to the sifter, is the dough kneadcr. The dough kneader is no new invention. As far back as 1760, a kind of dough kneader was constructed in France by one Salignac. It is described as consisting of a trough, inside which the dough was agitated by arms shaped somewhat like harrows. This machine is said to have been tested before a committee of the Academy of Sciences, who reported that in their presence dough had been prepared in fourteen to fifteen minutes. The bread baked from this dough is said to have been most satisfactory, but for some reason the machine never came into general use. For one thing, the power problem would have been almost insuperable to a baker in the France of those days. In general design this kneader approximated to the machines which have since done good work in bakeries all the world over. Salignac was quickly followed by another inventor, Cousin, also a Frenchman, who brought out in 1761, or thereabouts, a dough-kneading machine, which, however, had no better success than its predecessor. The first kneading machine which appears to have been in actual use in a bakery was constructed by a Paris baker of the name of Lembert, after whom it was called the Lembertine. Lembert is said to have been experimenting with this apparatus as early as 1796. Be that as it may, it was not brought out till 1810, when a prize of 1500 francs (£60) was offered by the Société d'Encouragement pour l'Industrie Nationale. This reward was won by Lembert, and his machine thereupon came into a certain amount of use in France. It is remarkable that France long remained the only country in which dough kneaders were employed, but even there their use was limited.
The Fontaine, another French kneader, called after its inventor, was first made in 1835. It had a certain success, but has long passed out of use. It appears to have been a copy to a great extent of the Lembertine. The objection against both these machines was that their blades, while exercising a mixing action, were deficient in kneading effect. Probably the first machine which achieved the task of efficiently replacing the work of human arms in sponge breaking and dough kneading was the Boland kneader. This was also a French machine, and dates back to about the middle of the 19th century. It is believed to have been first used in the Scipion bakery in Paris. It consists essentially of a trough, inside which revolve a pair of blades so arranged as to work somewhat like alternate screws: it is claimed for these blades that their action has the effect of tossing the dough backwards and forwards when it is slack, and of drawing it out when it happens to be stiff. It is further claimed that the blades are so shaped that their revolution has the effect of moving the dough from right to left and left to right in the trough. The machine is geared to give two speeds, the faster being suitable for sponge setting, while the slow and most powerful speed is intended for the doughing. The Boland machine has been widely adopted in other countries than France, and was certainly one of the first dough kneaders to be used in the United Kingdom. It was installed in the great Boland bakery in Dublin, where it proved a great success. The proprietor of this bakery, with which was also connected a flour mill, is said to have had his attention first drawn to this machine by the fact that its inventor was his namesake, though no relative.
The Deliry-Desboves dough kneader, also of French origin, and in general use in France, consists essentially of a cast iron trough, shaped somewhat like a basin, and turning on a vertical axis. The kneading arms inside the trough are shaped after the pattern of a lyre, and have the effect of first working up and then dividing the dough right through the kneading process. Two helical blades, which also form part of the mechanism, serve to draw out and aerate the dough, as effectively, it is claimed, as can be done by the most skilled operative. The force of the kneading operations can be regulated without stopping the machine. A thoroughly kneaded dough can, it is said, be made in this machine in twelve to fifteen minutes.
In Great Britain the type of machine that used to be most in favour was the trough within which the kneading arms worked on horizontal axis. The trough was either open or provided with a lid. The kneading blades were variously shaped, but generally were more or less straight, and were designed to both mix and aerate the dough. In some cases the kneading blades were worked on a single axis, in others two different sets of arms worked on two axes running parallel to one another. Generally the kneader was geared to two speeds, the fast motion being most suitable for sponge setting, and the earlier stages of dough-making, while the slower motion was intended to draw out and thoroughly aerate the dough. To discharge the dough, the trough was tilted by means of a worm and worm wheel, the latter being secured to the trough. Several variations of this type of kneader are still in use. The machine known as the "Universal" kneader consists of a trough set horizontally, within which rotate on horizontal axes a pair of blades lying in the same plane. These blades are curved and are geared together by means of differential spur wheels, with the object of running the two spindles at unequal speeds. The bottom of the trough is divided into two semi-cylindrical cavities, separated by a ridge. Each blade plunges into its own cavity, and the action of these arms tends, while pressing the dough against the sides and base of the trough, to bring it quickly back towards the centre. The differential speed has the advantage of effecting a more thorough mixing of the dough, as it brings together pieces of dough which have not yet been mingled, the blades pushing the dough from one cavity to the other. To hasten the kneading process it is desirable occasionally to reverse the motion by a turn of a hand wheel on the same shaft as the two pulleys. This wheel governs all the motions of the blades. The trough, which is set low, is tilted over, when the dough is ready, by an endless chain operated by a hand winch. The effort required for this operation is very slight, as the trough is balanced by two weights. The action of tilting does not interfere with the blades, which continue rotating until stopped by the hand wheel. The Universal kneader was designed to imitate as closely as possible the action of a pair of skilled human arms and hands, but of course works at a much greater speed.
Another form of dough mixer which is extensively used consists simply of a drum made of sheet steel supported by two A-shaped standards at a sufficient height from the floor to allow a trough to be run underneath to receive the dough when ready for the moulding board. In this drum are two tight-fitting doors. The interior is fitted with no blades or knives, but presents a free cylindrical space, with the sole exception that, set not very far from the circumference, there are several fixed rods passing from one side of the drum to the other. These act as mixers of the dough. The door is opened and the flour and water poured in, whereupon the door is again fastened and the drum is made to rotate. As the rotation proceeds, the dough begins to form, and being lifted up by the revolving drum falls by its own weight. In this process, which is repeated again and again, the dough is caught by and tumbled over by the rods, which act as mixers and take the place of the revolving arms of the trough kneader. The kneading action of the rotating arms is absent, but the steady tumbling over these rods appears to have a thorough mixing effect, and the dough is discharged from the drum in good condition for moulding. The time occupied for making a dough by this apparatus varies from four to six minutes. The advantages claimed for this machine are that it consumes comparatively little power, and that there is not so much danger of "felling" or over-kneading dough as in some of the machines with revolving blades. The compactness of this rotating drum mixer, often known as the Rotary mixer, recommends it on shipboard and in other places where space is limited.
Dough dividers and moulders
In the earlier days of machine bakeries the accurate dividing of dough, and still more the moulding of loaves by mechanical means, was considered an unattainable ideal. The first step in this direction was made by the Lewis-Pointon dough divider and weigher, which was intended for dividing and weighing out dough ready for the moulding table. In an ordinary way a baker who wishes to bake a batch of half-quartern or 2-lb loaves scales off 2 lb 2 oz. of dough for each loaf. The 2 oz. are a sort of insurance against light weight. The evaporation of moisture from dough in the oven is bound to reduce to some extent the weight of the baked loaf, but with normally baked bread, 2 lb 2 oz. in the case of half-quarterns, and 4 lb 4 oz. in the case of quartern loaves, is sufficient to ensure full weight. As the accurate scaling of dough requires some pains and trouble, it would be surprising if hand scaling were always accurate. The Lewis-Pointon machine can, it is claimed, be set to turn out lumps of dough of the exact weight required either for 1-lb, 2-lb, or 4-lb loaves. The apparatus does not measure the dough by weight but by volume by an ingenious piston arrangement. The machine when first put on the market was a little complicated, but its mechanism has since been simplified. It has been successfully worked on doughs of all descriptions, ranging from the tightest to those made with 20 gallons of water to the sack. The same firm which brought out this dough divider has also produced a dough-moulding machine, which has a wide range of work. In this apparatus the dough is introduced between a trough and a revolving table at a point on the outer periphery of the latter. The order of things observed in hand moulding is here reversed, as the trough, unlike the hand, is fixed, while the table revolves around a vertical axis. This table is sharply coned, and can be made to work the dough as much or as little as may be required. In working dough for tin or Coburg loaves only one trough is used, but for cottage loaves two parallel troughs are fitted, one taking the lower and the other the upper half of the loaf. In the latter case, a single piece of dough is fed into the machine and passed through an automatic splitter, the two portions being automatically carried into the troughs and simultaneously delivered at the other side of the machine ready to be put together. With doughs which require "handing-up," two machines may be used for moulding, the dough being automatically fed from the divider to the handing-up machine, and after a short proof passed through the finisher. But the moulding machine may also be used as a "hander-up."
Another ingenious dough moulder, known as the Baker-Callow, works on a rather different principle. Here the pieces of dough coming from the divider are fed into the moulder by a canvas band, and are worked between a large cylindrical roller and a vertically running canvas and leather belt. To prevent pieces from dropping through, and to assist the moulding process, a smaller roller is placed under and between the cylindrical roller and canvas belt. A wooden puncher also assists in working the loaves, which are finished by being rolled between a band and a special shaped wooden moulding. This machine delivers the dough in spherical shaped pieces. If intended for cottage bread they are at once placed on the dough table at the side, and one piece is put on the top of the other ready for the oven. It is claimed the machine will deal equally well with large and small pieces at the same time, so that the tops and bottoms can be made together. Should the machine be intended for tinned bread, a special attachment is used, into which the spherical pieces are delivered from the machine and rolled into cylindrical shapes, ready to be dropped into the pan. A capacity of sixty loaves per minute is claimed for this moulder.
Ovens. - The ordinary baker's oven is a vaulted chamber, about 10 ft. in length, by 8 ft. in width and 30 in. in height; it is constructed of brick or stone, and has a small door in front through which the oven is charged (by means of a "peel" or long wooden shovel) and the batch withdrawn. The furnace and fire-grate are often placed at the side of the oven door, but with the oldest ovens, which were heated by wood, there generally was only one door for the fuel and for the bread. Whether the furnace is heated by coal, as is usual in England, or by coke, as is often the case in Scotland, the oven mouth remains in the bakehouse itself; hence the stoking and scuffling must be carried out within the bakehouse. This is in many ways objectionable. For one thing, the fuel must almost of necessity be kept in the bakehouse itself, and it is obvious that the products of combustion are liable to get into the oven. In the old type of oven a flue was frequently placed on the other side of the furnace door, both furnace and flue being on the front of the oven. After firing the furnace, the oven is allowed to "lie down" for a certain time, and secure an even distribution of heat. The furnace and flue are then shut, and the oven charged, the batch being baked by the heat stored within the oven chamber. With ovens of this type, each batch of bread requires a separate firing. This kind of oven has undergone several improvements of detail, but the principle of internal heating, that is, of firing the furnace inside the bakehouse, has remained unchanged.
A new era in bakers' ovens began about the middle of the 19th century with the introduction of the "Perkins" oven, a system which, with slight modifications, has persisted till to-day. In this oven the baking chamber is heated by steam pipes. The latter consist of tubes of iron or mild steel which are partly filled with water and are hermetically sealed by welded ends. The pipes are arranged in two parallel rows, the one at the crown and the other at the sole of the oven. The pipes project at one end into the furnace, which is set at the back of the oven and is usually outside the bakehouse. This is termed an externally heated oven. As the ends of the pipes get red hot the water is converted into superheated steam, which being under high pressure soon raises the chamber to baking heat, say 450° to 500° F. In an oven of this description the heat can be continuously maintained, and batch after batch can be baked without refiring. The only drawback is that a flash heat cannot be raised. In another type of externally fired oven the heat is conveyed by flues placed at the bottom and top of the oven, which discharge into a chimney. Excellent results have been attained with ovens of this kind. The distribution of the heat can be well regulated; for instance, it is quite possible to build ovens to be cooler at the back than front, an arrangement which is useful when the bread is withdrawn by means of a hand peel. As the baker has to withdraw each loaf one at a time, it is clear that the withdrawal of the batch through the oven door must take time, probably not less than half-an-hour. Hence the bread drawn from near the oven's mouth may be underbaked as compared with that at the back of the chamber. The latter, on the other hand, may be overbaked and deficient in weight.
By means of a draw-plate, however, an oven can be expeditiously charged. This appliance consists of a sliding plate or tray, mounted on wheels running on rails, which is drawn out of the oven loaded with bread, and then returned. The plate itself is often made of iron, but one well-known oven is fitted with a withdrawable iron frame, in which are laid, edge to edge, tiles of a special make, which are cemented in place, and form a continuous baking surface. This seems an excellent arrangement, as the baker has all the advantages of a brick oven, that is to say, his bread is baked both on top and bottom by heat evolved from tiled surfaces, and the undoubted drawbacks incidental to baking bread on an iron surface are avoided. A draw-plate fitted to an oven capable of baking a batch made from a sack (280 lb) of flour can be run out, charged and run in again, in about two minutes. The draw-plate has the incidental advantage, by expediting the loading and discharge of the oven, of ensuring a more uniform baking of the batch, and therefore of minimizing the loss of weight. Some bakers have gone so far as to estimate the saving in this respect from the use of a draw-plate at half an ounce per 2-lb loaf. With decker ovens a double draw-plate may be used, the feet of the pedestal supporting the upper draw-plate running on a rail outside, but parallel to the rail on which the lower draw-plate runs. This arrangement, however, is more applicable to small than large ovens. Or the lower oven may be fitted with a draw-plate while the upper oven is served with a peel. The draw-plate being at a lower level than the sole of an ordinary oven, the upper deck may be worked with a peel without much difficulty.
The decker oven is, as its name implies, an oven built over another oven: in fact, sometimes a tier of three ovens is employed, placed one above the other. The object is to secure a double or treble baking surface without a very much larger outlay on fuel than would be necessary for one oven. It is easy to understand that a double or three decker oven might be constructed under conditions where it would be impossible to place two or three ordinary ovens side by side. Practical bakers are somewhat divided as to the actual economy of the decker system; possibly it is a question of management. The upper oven is heated by the gases which have passed under the oven beneath. A double-decker oven on the flue principle could be heated by three flues, one beneath the lower oven, another passing between the crown of the lower and the sole of the top oven, and the third over the crown of the upper oven. If a third oven were built over the second, then a fourth flue would pass over the crown of the third and top oven. In such an arrangement of flues the distribution of heat to the ovens would be fairly equal, but no doubt the lower oven would be the hottest. In addition to the flues, which should be straight and accessible for cleaning, there ought also to be auxiliary flues by which heat may be allowed to pass dampers to the upper portions of the series of ovens. In this way the heat of the upper oven or ovens can be regulated independently to a great extent of the bottom oven. The power of regulating the heat of the ovens is very necessary, because a baker doing what is called a mixed trade, that is to say, producing cakes and pastry in addition to bread, must work his ovens at varying temperatures. Cakes cannot be baked at the heat (about 450° F.) required by a batch of household bread. The richest fancy goods, such as wedding and Christmas cakes, require the coolest ovens. Flue ovens are best worked with coke, as coal is apt to choke the flues; retort coke is recommended in place of oven coke. An oven should be fitted with some kind of thermal register, and both high-temperature thermometers and pyrometers are used for this purpose.
(G. F. Z.)
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)