and is then called "light." It is not a good word, for whether a loaf is "light" or "heavy" it weighs the same, except in so far as it may be too wet if it is not sufficiently baked; the difference will consist in the size and relative weight of the two, and not in the actual weight. A "light" loaf is puffed up to look larger.
All goods, therefore, made with baking-powder, should be put into the oven as soon as possible after the moistening ingredient is added, or the result will be a very indifferently aerated cake or loaf. This rule applies generally to all kinds of baking-powders, cakes, pastry, or bread.
Another rule is to use the coldest water and to mix it in a cold place. We have seen that the rising of a loaf depends on the sudden expansion by heat of the air it contains, and the greater the difference between the coldness of the air as it goes into the oven, and the heat of the oven itself, the more it will rise, always provided that the oven is not so fierce as to scorch and stiffen the crust before the inside has had time to be heated. Cakes can be made light with snow instead of water, even with no baking-powder, because of the extreme coldness of the air that is mixed into them.
In this kind of bread-making the gas is formed in the dough, but not of it, as with yeast, and, therefore, the taste of the wheat is more perfectly preserved.
Other Acids used.—When hydrochloric acid is used, instead of tartaric acid, or cream of tartar, it combines with the soda to form chloride of sodium, better known as common salt. It is more difficult to mix than the dry acid, but it has the advantage that common salt is always harmless, while tartrate of soda is an aperient, having exceptional action upon a few constitutions. There are persons who cannot eat bread made with baking-powder; this is probably the reason. Such an idiosyncrasy is, it must be confessed, very rare; and the commercial acid (hydrochloric) often contains arsenic in small quantities, which is a very undesirable element for bread-making purposes, and at the present time it is very seldom used for aërating bread or anything else. A commoner objection to baking-powder is that it leaves a soapy taste, resulting from an excess of soda. Excess of acid is far less objectionable and less common. Other acids may be used, as, for instance, sour milk, or butter-milk, which makes excellent bread with bicarbonate of soda. Liebig recommended acid phosphates of lime, chloride of sodium, and bicarbonate of soda, which very gently and slowly evolves the gas, and, therefore, makes better bread than substances that effervesce quickly and are soon still. Sesqui carbonate of ammonia is also used by bakers to make cakes. It is extremely volatile, and must be kept in a tightly-stoppered bottle.
Eggs act in two ways. They increase the tenacity of the dough, so that it better retains the air, and when they are beaten to a froth, they carry a good deal of air into the cake.
