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the condition and quality of the flour. In St. Louis the standard grades are, in descending order of quality and whiteness, Patent, Extra Fancy, Fancy, Choice and Family. Besides improving in color, flour also yields a larger loaf as it grows older. When properly stored, the only loss is in the power of absorbing water. Flour readily absorbs undesirable odors, such as those of pine wood, kerosene, and smoked meats.

Human Foods Made from Wheat.—Not only does wheat have great superiority in sustaining life, but a large variety of healthful, palatable and attractive foods are made from it, either wholly or in part. Breads, pastries, crackers, breakfast foods and macaroni, of almost endless variety in composition, form and appearance are now found on table and market. Many of these have a comparatively recent origin, while others of a more remote origin have come into general use only in recent times. Wheat foods alone do not furnish proper nutrition for the body, for an amount sufficient to supply the requisite protein would furnish more than the requisite carbohydrates.

Bread is the oldest and most important product made from wheat. It supports life better than any other single food except milk, and it is the most staple food of modern civilization. The baking of bread is older than history. The prehistoric Swiss Lake Dwellers baked bread as early as the Stone Age. From the burnt specimens that have been disinterred, it was found that they did not use meal, but that the grains were more or less crushed. The ancient Egyptians carried the art of baking to a high perfection. Lippert maintains that the baking of leavened bread was practiced longest by the Egyptian and Semitic peoples. The Jews, however, still hold one feast in memory of the old form of unleavened bread. The bread of the Homeric Greeks is supposed to have been a kind of unleavened cake baked in ashes. The ancient Greeks had at least 62 varieties of bread. An oven containing 81 loaves of bread similar to the bread of modern times was found in Pompeii.

"Strong" and "Weak" Bread Flour.—The higher the gluten content of flour, the more water it will absorb in the dough; consequently it will yield more bread, and is known as "stronger" flour. Baker's bread is sold according to its weight in the dough, and a barrel of hard-wheat flour will make several pound loaves more than a barrel of soft-wheat flour. The weight of the dough and the size of the baked loaf are largely determined by the quantity and quality of the gluten. One hundred pounds of flour will make about 160 pounds of dough and about 140 pounds of bread. The flavor of the bread depends to a great extent upon the gluten and oil of the flour. These two compounds give the desirable "nutty" character so prominent in hard-wheat bread.

At the present day, first-class bakers generally use but one grade of standard flour for making bread. Every barrel of such flour is numbered at the mills where it is made, and if the quality should happen to be inferior, a report is made to the mill, and from the number of the barrel the mill determines the date when the flour was milled, its composition, and whether other similar complaints have been made concerning the same flour. The difficulty is thus located and remedied. Flour of the first-class standard grades costs from 10 to 25 cents per barrel more than other flours which are often just as good, and which are frequently used, although less reliable.

Yeast.—The making of leavened bread requires the use of yeast, a fungous plant. Three forms of yeast have been used in making bread: Brewer's yeast, which is that used by brewers in malting; German yeast, also called dried or compressed yeast, which consists of sporules only, and contains little moisture and no gas; and patent yeast, which is a thin watery liquid prepared from an infusion of malt and hops.

Mechanical Processes.—The most primitive method of making bread consisted merely in soaking the whole grain in water, subjecting it to pressure, and then drying it by natural or artificial heat. Perhaps the simplest form of bread and the rudest baking of modern times are found in the Australian "damper." Dough composed of flour, salt and water is made into cakes, which are baked in the dying embers of a wood fire. There have been no great modern improvements in machinery for making bread. A quarter of a century ago it was still made and baked much as it was in ancient Greece. The sponge was mixed and the dough kneaded by machinery, but as yet there had been failure to make loaves by machinery. Except in the formation of loaves, perhaps, there seem to have been no marked improvements during the last 25 years.

The Modern Bakeshop.—The statutes generally require bakeshops to be inspected and kept in healthful condition. Each baker contracts by the year with a specialist to keep insects out of his establishment. The specialist visits the place at least once every three months whether insects appear or not. He receives a notification if but a single bug appears. His work is performed so thoroughly that it is exceptional if a bug is seen at all.

The following description is of a representative, moderately large-sized bakeshop which uses from 25 to 60 barrels of flour per day, and daily bakes from 7,500 to 20,000 loaves of bread. Each day the flour for the next day's baking is sifted. The sifter consists of a rotary brush running over a sieve, and it sifts the flour as fast as an attendant empties the barrels, about one each minute. All machinery is operated by electricity. The bakeshop is three stories high, and the sifting is done on the third floor. The sifted flour descends to a bin under the ceiling of the second floor. Under this bin, and on the second floor, is located the mixer. It has a capacity of four barrels of flour. The water, milk, lard, sugar, yeast, malt extract and salt are first placed into the mixer, and then the flour is added. Two parts of moisture are used to one of flour. Compressed yeast is used, and more is required in winter than in summer. The arms of the mixer revolve at a comparatively slow rate, about once in every two seconds, throwing the dough from side to side. The mixing operation requires 30 minutes. A large spout extends through the floor to the room below. As soon as the dough is in proper condition, the mixer is turned over, and the bread descends through' the spout to the floor below, into the large bread trough which has been rolled under the spout. In this trough it rises about three hours. Thus far no hand has touched the bread, but some handwork now becomes necessary. Enough dough is weighed for 12 loaves, which are then cut out at one operation with an air pressure machine. After the loaves are cut they are molded by being run through the molding machine, of which the capacity is theoretically 60 loaves a minute, but in practice only about 40. The loaf is molded or rolled by an endless apron underneath, which carries it along in a rolling motion, and by a fixed top-piece, which is lined with sheep's wool in order to prevent sticking. The loaf travels about three feet. This is the Corby patent. After molding, the bread is placed in pans to rise. The best temperature for this is from 70 to 75° F.

The bread is baked in a continuous oven fired by coal. The temperature for baking should be from 450 to 550° F., so that the interior of the loaf will be at the boiling point, 212° F. When baked, the loaves are tipped out of the pans upon racks to cool, after which they are ready for sale. It is by varying the proportion of ingredients, the quality of the flour, the size of the loaf, and the time of rising and baking, that each baker produces bread of a quality in accord with his own ideas. The amount of bread produced from the same flour also depends to a great extent upon such variations. Rolls are cut by a special machine, 36 at a time. They are placed to rise, after which they are shaped by hand. They rise again, and then are baked. There are also special machines for mixing and cutting cake.

Kinds of Bread.—Common or leavened bread needs no description. Unfermented or unleavened bread is of two kinds: That in which substitutes producing carbonic gas are used in place of yeast, and that in which nothing but flour and water, and perhaps salt, are used. The former, also known as a vesiculated bread, is made in three different ways: (1) Carbonic acid is developed within the dough through fermentation of the flour; (2) the dough is mixed with water that has been previously mixed with carbonic acid; or (3) carbonic acid is disengaged from chemicals introduced into the dough. Maryland, or beaten biscuit, is an interesting variety of unleavened bread. Air is introduced into the dough by means of folding or pounding. These small portions of air expand in the baking, making a porous bread.

The original graham bread was made from graham flour without yeast or any of its substitutes. The dough was left standing several hours before baking. It was heavier than ordinary yeast bread, but somewhat porous, probably owing to fermentation started by bacteria accidentally present in the flour and acquired from the air. It was sweet, and by no means unpalatable. It is now baked like common bread.

Gluten bread is made from strong flour and water. The dough is pressed and strained under a stream of water until the starch has been worked out, when it is kneaded again and baked. It gives a light and elastic loaf which is often prescribed for diabetic patients. Aerated bread, which has had considerable popularity in London, is made by a method invented in 1856. The water used is charged with carbon dioxide gas. Another form of bread that has been made is the salt-rising bread. Hot water and cornmeal are mixed into a stiff batter, which is left at blood heat until it is fermented. The ferments originally present or acquired from the air produce fermentation, which leavens the batter. A thick sponge is then made from wheat flour and warm milk in which a little salt and sugar have been dissolved. This sponge and the fermented batter are thoroughly kneaded together and set in a warm place for several hours.

Chemical Changes and Losses in Baking.—Below is given in per cents the average composition of white bread and of the flour from which it was made.

[table]

In mixing the bread, the water was added, the fat was added as butter or lard, and the ash was added as salt. The protein and carbohydrates which were lost went to nourish the yeast plant. This feeds mainly on the sugar in the dough, and in its growth gives off alcohol and carbon dioxide gas. The gas and the generated steam expand with heat, force their way through the dough, and thus lighten it. Yeast also acts as an agency to turn starch into sugar. It is the tenacious quality of gluten (wanting in other than wheat flours, however nutritive), which retains the gas in its tendency to escape. Being elastic, the gluten expands, and the bread becomes porous.

"In bread making the action of the yeast and heat results in: (1) The fermentation of the carbohydrates and the pro

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