From experiments in which I have been employed, with the assistance of skilful bakers, I am authorised to state, that without the addition of alum, it does not appear possible to make white, light, and porous bread, such as is used in this metropolis, unless the flour be of the very best quality.

Another substance employed by fraudulent bakers, is subcarbonate of ammonia. With this salt, they realise the important consideration of producing light and porous bread, from spoiled, or what is technically called sour flour. This salt which becomes wholly converted into a gaseous state during the operation of baking, causes the dough to swell up into air bubbles, which carry before them the stiff dough, and thus it renders the dough porous; the salt itself is, at the same time, totally volatilised during the operation of baking. Thus not a vestige of carbonate of ammonia remains in the bread. This salt is also largely employed by the biscuit and ginger-bread bakers.

Potatoes are likewise largely, and perhaps constantly, used by fraudulent bakers, as a cheap ingredient, to enhance their profit. The potatoes being boiled, are triturated, passed through a sieve, and incorporated with the dough by kneading. This adulteration does not materially injure the bread. The bakers assert, that the bad quality of the flour renders the addition of potatoes advantageous as well to the baker as to the purchaser, and that without this admixture in the manufacture of bread, it would be impossible to carry on the trade of a baker. But the grievance is, that the same price is taken for a potatoe loaf, as for a loaf of genuine bread, though it must cost the baker less.

I have witness, that five bushels of flour, three ounces of alum, six pounds of salt, one bushel of potatoes boiled into a stiff paste, and three quarts of yeast, with the requisite quantity of water, produce a white, light, and highly palatable bread.

Such are the artifices practised in the preparation of bread,[45] and it must be allowed, on contrasting them with those sophistications practised by manufacturers of other articles of food, that they are comparatively unimportant. However, some medical men have no hesitation in attributing many diseases incidental to children to the use of eating adulterated bread; others again will not admit these allegations: they persuade themselves that the small quantity of alum added to the bread (perhaps upon an average, from eight to ten grains to a quartern loaf,) is absolutely harmless.

Dr. Edmund Davy, Professor of Chemistry, at the Cork Institution, has communicated the following important facts to the public concerning the manufacture of bread.

"The carbonate of magnesia of the shops, when well mixed with flour, in the proportion of from twenty to forty grains to a pound of flour, materially improves it for the purpose of making bread.

"Loaves made with the addition of carbonate of magnesia, rise well in the oven; and after being baked, the bread is light and spongy, has a good taste, and keeps well. In cases when the new flour is of an indifferent quality, from twenty to thirty grains of carbonate of magnesia to a pound of the flour will considerably improve the bread. When the flour is of the worst quality, forty grains to a pound of flour seem necessary to produce the same effect.

"As the improvement in the bread from new flour depends upon the carbonate of magnesia, it is necessary that care should be taken to mix it intimately with the flour, previous to the making of the dough.