A treatise on the art of making good wholesome bread of wheat, oats, rye, barley and other farinaceous grains / Exhibiting the alimentary properties and chemical constitution of different kinds of bread corn, and of the various substitutes used for bread, in different parts of the world

by Friedrich Christian Accum

Analysis of Bread Flour.

On examining bread corn, for instance wheat, we perceive an outside coating, which after the grain has been soaked in water, may readily be peeled off. This forms the bran of the flour. Immediately under it, is that part of the grain which affords the coarsest flour, it is soft to the touch, and not easily reduced to an impalpable powder, and of a sweetish taste. This constitutes about one half of the grain. Underneath this substance lies what is called by millers, the kernel or heart of the wheat, namely, a hard mealy substance, almost transparent. This part of the grain is capable of being speedily reduced to an impalpable powder, it ferments more readily than the outer layers, and it is this which produces the finest and best kind of wheaten flour. Such is the mechanical constitution of the grain. When chemically examined we find that the flour of wheat, rye, and barley, is composed of three ingredients, or immediate constituent parts, which may be separated by simple processes, viz. starch, gluten, and saccharine mucilage. The proportion of these differ materially in different kinds of corn. The method of separating them is as follows:

Make any quantity of wheaten flour into a stiff paste with cold water, and let it be kneaded and wrought in the hands under water; or put the flour into a coarse linen bag, and knead it between the hands whilst a small rill of cold water is suffered to pass over it. The water will carry away the starch in the form of a white powder, and the dough become more and more elastic, in proportion as the water carries off the starch; continue kneading the mass till the water runs off from the kneaded dough colourless. It will also be observed, that in proportion as the water carries off the starch, the paste in the bag assumes a more grey colour, less brilliant, as it were semi-transparent, and of a softer consistence, but, at the same time, more tenaceous, more viscid, more gluey, and more elastic.

Thus the flour is separated into three substances, by a method incapable of decomposing or altering any of its immediate constituent parts. The starch is precipitated in a white powder at the bottom of the water, from which it may readily be separated by suffering it to subside, and the supernatant liquid, contains in solution the saccharine mucilage; this may be obtained in the form of a syrup, by evaporating slowly in a warm place the clear decanted fluid; and the third substance, the gluten, remains in the bag, in the state of a soft, cohesive, and elastic substance.

In a similar manner the analysis of any species of bread corn may be effected.

QUANTITY OF FLOUR OBTAINABLE FROM VARIOUS KINDS OF CEREAL AND LEGUMINOUS SEEDS EMPLOYED IN THE FABRICATION OF BREAD, AND DIFFERENT KINDS OF FLOUR MANUFACTURED FROM WHEAT.

The Board of Agriculture, in order to ascertain what each of the various sorts of grain employed as substitutes for bread-corn would produce, when ground into flour, with only the broad bran taken out, caused a bushel of each of the undermentioned sorts of seeds to be ground for their inspection: the weight of the grain, as well as the bran and the flour, was as follows:

		Weight	Weight
	Weighed.	of Flour.	of Bran.
One Bushel of	lb.	lb. oz.	lb. oz.
Barley	46	38 10½	5 10½
Buckwheat	46¼	38 9	5 5
Rye	54	43 0	9 5½
Maize	53	44 0	8 10½
Rice	61¼	60 5	0 0
Oats	38¼	23 5	13 10½
Beans	57¾	43 5½	12 5
Pease	61¾	47 0	12 5

A bushel of wheat, upon an average, weighs sixty-one pounds; when ground, the meal weighs 60¾ lbs.; this on being dressed, produces 46¾ lbs. of flour of the sort called seconds, which alone is used for the making of bread in London, and throughout the greater part of this country; and of pollard and bran 12¾ lbs., which quantity, when bolted, produces 3 lbs. of fine flour; this when sifted produces in good second flour 1¼ lb.

		lbs.
The whole quantity of bread-flour obtained from the bushel of wheat, weighs		48
	lbs.
Fine pollard	4¼
Coarse pollard	4	11
Bran	2¾
		—
The whole together		59
To which add the loss of weight in manufacturing the bushel of wheat		2
		—
Produces the original weight		61

REASON WHY OATS, PEASE, BEANS, RICE, MAIZE, MILLET, BUCKWHEAT, AND OTHER NUTRITIVE GRAINS CANNOT BE MADE INTO LIGHT AND POROUS BREAD.

Every person is acquainted with the difference there is between light well fermented bread, and that which is sodden, heavy, and badly risen, and the decided preference given to the former over the latter, as the most palatable, and easy of digestion.

The only substances for making loaf bread, by which term is meant, bread which is light, white, and porous, is the flour of wheat; and it is to the larger quantity of gluten, that wheat flour owes the property of being converted into loaf-bread. The average quantity of gluten contained in wheat flour, amounts to about one-fifth of the whole weight of the meal; but it varies in quantity in different kinds of wheat, according to the soil and season in which the corn has been reared, culture, and various other circumstances. Wheat kept in damp storehouses affords scarcely any gluten, and hence, in proportion as the flour of wheat is altered and deteriorated, which happens, as it is known, when it is kept too much compressed, without being occasionally stirred up and aired in hot and close granaries; in a word, as it undergoes a chemical change, its property of making good bread is diminished; and chemical analysis shows the quantity of gluten has become lessened under such circumstances; and when it is greatly diminished the meal forms no longer a tenaceous ductile dough. The spoiled flour produces a kind of bread which is heavy, harsh, and difficult of digestion.

The greater the proportion of gluten, the easier the panification of bread-flour is effected, and the better is the bread. The wheat of the South of Europe generally contains a larger quantity of gluten, and is therefore more excellent for the manufacture of Maccaroni, Vermicelli, and other alimentary substances, requiring a glutenous paste.

Sir H. Davy found the flour of the wheat of this country to consist of from twenty to twenty-four per cent. of gluten. Barley contains six, and rye five per cent. of gluten.

We may now understand why potatoes, rice, beans, pease, buckwheat, millet, oats, and other nutritive cereal grains, abounding in starch, cannot be made into light and porous bread, although they are well calculated for being made into wholesome puddings, and why they only form crude, heavy, insipid cakes, when made into dough and baked, and not light porous loaf-bread.

In further confirmation of this statement it may be remarked, that if gluten of wheat, or only a portion of wheaten flour be incorporated by kneading with the before-named kinds of flour, a fermentable cohesive paste is produced, from which perfect bread may be made.