Protein 11.4 per cent Fat 1.0 "
Carbohydrate 75.1 "
Fuel value 1610 Cal. per pound 100-Calorie portion 28 grams (1 ounce)
The protein occurs in the form of gluten, which has the property of stretching and expanding, and which makes the framework of the loaf of bread, since it retains the air and carbon dioxide, and hardens when baked. The protein of oats and corn lacks this property, and therefore oatmeal and corn meal give a very different type of bread. Rye flour contains gluten, and the rye loaf therefore resembles the wheat loaf.
Wheat and flour differ largely on account of the difference in the amount of gluten, and the gluten itself varies in quality with the variety of wheat.
[Ill.u.s.tration: FIG. 52.--Experiment ill.u.s.trating the effect of the kind of wheat upon the size of the loaf. _Courtesy of Utah Agricultural College._]
Figure 52 shows the result of an experiment with flour made from different kinds of wheat, all the other factors in the bread making being identical.
This effect of the difference in the composition of the flour is very striking. Again, the same variety of wheat will differ from season to season, and the time of planting, also, affects the quality of the grain.
The time of planting and reaping gives us two cla.s.ses of wheat and flour, the winter and spring. Winter wheat is sown in the fall and obtains its first growth before winter, living through the winter in those lat.i.tudes where the climate is sufficiently mild, being harvested in early summer.
Spring wheat is sown in the spring and harvested late and it is the wheat of the great flour-producing state, Minnesota. The difference in the composition of the two wheats is shown in this table.[13]
=============================================================== | WATER | PROTEIN | FAT |CARBOHYDRATE| ASH | --------------------|-------|---------|-----|------------|-----| Wheat | | | | | | Spring varieties | 10.4 | 12.5 | 2.2 | 73. | 1.9 | Winter varieties | 10.5 | 11.8 | 2.1 | 73.8 | 1.8 | ---------------------------------------------------------------
Note that the spring wheat contains more protein and therefore more gluten. The flour from spring wheat is creamy in color, granular to the touch, has more gluten, and is known as a _strong_ flour. Flour from winter wheat is somewhat whiter in color and smoother to the touch, feeling more like cornstarch, and if a portion is squeezed in the hand, it retains the imprint of the fingers. It has less gluten, more starch, and is known as a _soft_ flour. This type of flour is sometimes called "pastry flour," the smaller percentage of gluten making it more desirable for pastry or cake than the stronger flour.
Flour manufacturers and bakers are constantly experimenting to find the best possible varieties and combinations of varieties for bread flour.
Some difference of opinion exists, but a combination of winter and spring wheat in flour is considered the best for bread by some authorities.
We must learn to like a creamy color in bread, for this means the presence of more gluten. To summarize: a good bread flour contains a large percentage of gluten, is creamy in color, and granular to the touch.
=Manufacture of flour.=--Modern machinery has taken the place of the old-time stones in the grinding of flour, although the two main divisions of the process remain the same, these being the crushing of the grain and the sifting out of the coa.r.s.e portion. Milling now includes many stages in the process not possible with the cruder machinery of former times, and the present effects a greater number of separations and permits the miller to make a greater variety of products.
[Ill.u.s.tration: FIG. 53.--A dissected grain of wheat. _Courtesy of Washburn Crosby Co._]
Figure 53 shows a dissected kernel of wheat, with its five layers of bran.
Within these at _B_ is a sh.e.l.l of glutinous matter, yellowish and of flinty hardness, and within this, but not sharply divided from it, lie the starch granules in a network of woody fiber, the germ lying at _A_. The milling process must remove the bran coats and the germ, and crush and roll the remaining portions to the necessary fineness. The germ if allowed to remain affects the color and keeping properties. The breaking and rolling are accomplished by steel machinery, and the final sifting is done through silk bolting cloth. By the new machinery about 70 per cent of the wheat is saved for food, 30 per cent being bran, "shorts," and other by-products used chiefly for cattle feeding.
Figure 54 shows the vertical section of a mill, simplified in the drawing that all the steps of the process may be clear. The diagram does not, of course, show the actual arrangement of the mill.[14]
[Ill.u.s.tration: FIG. 54.--Simplified diagram of a flour mill. _Courtesy of the Washburn Crosby Co._]
The typical parts in a modern flour mill are as follows: (1) Scales, for weighing wheat as it is received. (2) Receiving separator, for separating other kinds of seeds from wheat. (3) Storage bins, for reserve supply of wheat in advance of mill requirements. (4) Mill separator, for further separating foreign seeds from wheat. (5) Scourer, for removing dust from wheat kernels. (6) c.o.c.kle cylinder, for removing all round seeds. (7) Wheat washer, for thoroughly cleansing the wheat. (8) Wheat dryer, for drying wheat after washing. (9) 1st break rolls, for rupturing bran, enabling bran and germ to be separated from interior. (10) 1st break scalper, for sifting middlings through bolting cloth to separate from bran. (11) 2d break rolls, for further loosening the middlings from bran.
(12) 2d break scalper, for separating more middlings from bran. (13) 3d break rolls, for further loosening middlings from bran. (14) 3d break scalper, for final separation of middlings from bran. (15) Bran duster, for dusting low grade flour from bran. (16) Bran bin, for packing bran for shipment. (17) Grading reel, for separating middlings by sifting through various sizes of bolting cloth. (18) Dust collector and purifier, for cleaning and purifying middlings by air and sifting. (19) Smooth rolls, for grinding purified middlings very fine to flour. (20) Flour bolter, for sifting flour from purified middlings. (21) 2d reduction rolls, for further grinding of purified middlings. (22) Flour bolter, for separating flour from purified middlings of second grading. (23) Flour bin and packer, for packing flour for shipment. (24) Elevator, for raising products to the various machines.
=Other forms of flour.=--There has been much discussion of entire wheat flour _versus_ white flour, and the practical conclusions are as follows: the bread from whole wheat flour compares favorably with that from white flour (see Fig. 51), but this material is slightly less available for digestion than the material of the white flour. The mineral content is higher, and when the income is so limited that this cannot be furnished in milk, green vegetables, and fruit, whole wheat bread should be used. It makes a pleasing variety, too, for any table.
_Graham flour_ is a coa.r.s.e flour, containing the outer bran. It is useful for its effect upon the intestines in case of constipation, but has to be avoided by some people on account of its irritating effect. White flour may have coa.r.s.er material mixed with it, for variety in bread making, such as rye or Indian meal, or graham flour.
=Yeast in bread.=--Yeast is put into bread dough in order to produce carbon dioxide gas to lighten the whole ma.s.s. It is studied in the chapter on preservation of fruit, but in bread making we need to foster its growth instead of destroying it as, you will recall, we found necessary in preserving. You can easily reason out for yourself just how this should be done, especially after performing the experiments with yeast.
If yeast is in good condition, it has little effect on the flavor of bread, even if used in a rather large quant.i.ty to hasten the process.
The best forms of yeast now in use are the compressed and dried cakes, the former needing to be fresh, the latter keeping the vitality of the yeast cells for a long time. Liquid yeast may be made at home, but it is somewhat uncertain unless made with great exactness, and less easy to manage on the whole than the other forms.
=Proportions of the ingredients.=--One part of water to three of flour, or one cup to three of flour for a loaf, is an average proportion. The practiced bread maker will vary this slightly to suit the variations in the flour from time to time, but it is a safe rule for the beginner to follow. Spring wheat flour requires somewhat more water than the winter wheat, or the blend of the two. _Salt_ should be used sparingly, for although it improves the flavor of the loaf, salt is a preservative which r.e.t.a.r.ds or prevents the growth of lower organisms, and in the case of bread it acts therefore as a check to fermentation. One teaspoonful to a loaf is the largest amount that it is best to use.
The quant.i.ty of _yeast_ depends upon several conditions. The larger the amount of yeast used, the shorter is the time of rising, and as many as two compressed yeast cakes may be used to one loaf if it is necessary to hasten the process, without any perceptible effect on the color, texture or flavor. If a very large amount of yeast is used, the bread is "crumbly," and a difference in flavor will be noticed. A smaller amount may be used if time is allowed for the rising, even 1/8 cake of compressed yeast to a loaf, if the bread is to rise over night in warm weather. It must be remembered that, if the rising process is too prolonged, other organisms have a chance to work, and the bread may sour.
A small amount of _sugar_ hastens fermentation, and from one to two teaspoonfuls to a loaf may be used. Many people prefer the flavor of bread with no sugar, however. Some bakers use malt extract both as a yeast food to hasten fermentation and for its effect upon the flavor.
_Fat_, or _shortening_, should be sparingly used, not more than one or two teaspoonfuls being allowed to a loaf. If you study a number of bread recipes, you will see that this ingredient varies more than the others. As a matter of fact, if the flour is of good quality and the bread well made, this ingredient is not necessary (in loaf bread at least), although it seems to improve the quality of biscuit and rolls.
=Methods of mixing and the rising of bread.=--Dissolve the yeast in a portion of the liquid, stir this mixture into the remaining liquid, add half the flour, and beat the mixture thoroughly at this stage. Add the sugar if any is to be used. When this soft mixture, called the "sponge,"
becomes full of bubbles, add the salt, the shortening if used, and the remaining flour. Knead the dough by the hand, or by the machine, for about ten minutes, or until it is smooth and elastic. Put it into a greased bowl, cover the bowl, and allow the dough to remain until it doubles its bulk. Some bread makers knead in all the flour at the first, and obtain a good result. The first rising is more rapid, however, and experience seems to prove that the results are better on the whole with the sponge. Cut the dough down, knead again, using as little flour as possible. Shape into loaves, place the loaves in greased pans, cover, and leave again until the loaves double their bulk, when they are ready for baking. If left too long, the bubbles of gas become too large.
_Temperature_ and _time_ are important, in this matter of mixing and rising. The process may be shortened to five or six hours, including the baking, or lengthened to twenty-four by the choice of the amount of yeast and the temperature. The shorter process is the better, on the whole.
After reading over the sections of the chapter on preservation of fruit, performing the yeast experiments, and discussing the results, you will be able to answer these questions:
1. What should be the temperature of the ingredients when the bread is mixed?
2. If milk is used, how may the souring of the milk be prevented?
3. What temperature will you secure for the bread while it is rising?
4. If an emergency occurs, and the dough cannot be kneaded or baked at the moment it is ready, what can be done? Can you think of two expedients?
=A few suggestions.=--The kneading stretches the gluten and long kneading gives a fine grain. In such a recipe as that for the making of Parker House rolls, a very delicate quality results from a protracted process; one old-fashioned housekeeper recommends a half hour"s kneading three times. Fortunately a sufficiently good bread or roll may be made by ten or fifteen minutes" kneading at a time.
Bread dough may be cut or stirred with a large knife in place of the kneading, and this is a good method to teach to those who live in crowded s.p.a.ce and find it difficult to have a perfectly clean kitchen and proper utensils. With this method the dough must be softer, and it remains in the bowl until it is turned into the baking pan. The resulting loaf is somewhat moist, and not fine-grained, but the flavor is good.
Brushing the surface of the dough in the bowl or pan with water or milk will prevent the formation of a dry crust on the top.
=Baking the bread.=--The temperature of the oven should be steady, and about 380 F. An authority recommends 180 C. (355 F.) when the loaf is put in, rising to 220 C. (425 F.).[15] The amount of flour for one loaf has been given. A loaf this size should be baked in a pan 8-1/2 to 9 inches 3-1/2 to 4 3 to 3-1/2. The material of the pan is not of great consequence. Tin gives good results, a longer time being required for baking in a granite pan. A loaf should bake about one hour. (See Fig. 55.)
[Ill.u.s.tration: FIG. 55.--A few loaves of bread. _Courtesy of the Dept. of Foods and Cookery, Teachers College._]
_Rolls and biscuit_ may be shaped in many ways. (See Fig. 56.) How will the baking differ from that of the loaf?
[Ill.u.s.tration: FIG. 56.--Rolls of different shapes. _Courtesy of the Dept.
of Foods and Cookery, Teachers College._]
=Care of bread after baking.=--Remove from the pans, cool on a rack, place in tin box or stone jar, and cover with paraffin paper.
_Uses of stale bread._--Bread that has become too dry may be freshened by moistening the surface and heating in the oven. Bread may be used for toast, croutons for soup, escalloped dishes, puddings, crumbs for coating other food materials, and may be made into cups for holding other materials.
EXPERIMENTS AND RECIPES
_A. Experiment with gluten._
_Materials._--1 cup of flour, a 10-inch square of cheesecloth, a piece of string, a pan or tin or granite plate.
_Method._--Tie the flour in the cheesecloth, and wash it, preferably under the faucet, until the starch is washed out. Remove the gluten, stretch and knead into a ball. Place the ball on a pan in the oven. Note results. Note temperature of oven, if possible.
_B. Experiments with yeast._
1. _Materials_, (_a_) 1 cake of yeast dissolved in 1/3 of a cupful of lukewarm water with water added to make 1/2 cupful, (_b_) 1/4 cup water and 1/4 cup flour stirred together + 1 tablespoonful of mola.s.ses. Divide this mixture into three parts.