This section is from the book "Mrs. Allen's Cook Book", by Mrs. Ida C. Bailey Allen. See also: The Conscious Cook: Delicious Meatless Recipes That Will Change the Way You Eat.
The first important thing is the yeast. This is made up of minute plants, the success of the finished loaf depending upon their proper growth; and just as you coddle your rubber plant or Boston fern, the yeast plants must be nurtured until they have grown sufficiently. This may be judged by the amount the bread has risen. The growth of yeast, and, therefore, the rising of bread, demands close attention to temperature. Sudden chill is disastrous to yeast, the growth of which is checked by a radical drop in temperature. On the other hand, too great heat also causes unsatisfactory results, because at any temperature above ninety-five, various undesired organisms are sure to develop, which will give the bread a sour flavor. The proper temperature for the growth of yeast is from seventy to ninety-five degrees Fahrenheit.
In summer lower temperature is preferable, while in winter, when the flour is cold, higher may be used.
Many women say that they buy baker's bread because it is consistently good. The reason for this is that the baker always uses exact measurements, and fermentation is produced at a temperature regulated by the thermometer. There is no reason why every housekeeper should not use a thermometer in making bread as well as in preparing other foods. The woman who puts her bread to rise on the radiator, for instance, will find that the temperature will register from a hundred and fifty to two hundred degrees, and only somewhat lower if a wooden board is placed beneath the pan. If the bread is put next the radiator, it becomes too hot on one side, unless turned frequently, and if put on the back of the stove when the fire is at all hot, the heat is again directed unevenly. In hot weather the rising generally takes care of itself, but the only accurate method that I have ever found for winter use is to raise the bread over warm water. The dough should be placed in an enamelware bowl which fits over the top of a large stock-pot. The pot should then be filled with water at a hundred degrees, just full enough so that the enamelware pan touches the water when set in the pot. A lid is then placed over the dough and the whole set in the fireless cooker. Or if a fireless cooker is not at hand, the dough may be kept in a warm place just the same if the water is changed two or three times during the rising process.
Compressed yeast is very inexpensive and produces uniform results. However, to do good work it must be fresh, and should be of an even, light sand color with no dark streaks; it should break crisply; if there is any doubt about its freshness it should be dropped into a third cupful of tepid water, containing a tablespoonful of sugar. If fresh, bubbles will come at once to the surface. If they do not, the yeast should not be used. As compressed yeast works more rapidly than dry yeast, and as bread can be made from it with most excellent results without first making a sponge, it is the most satisfactory kind to use when one is near a market and can buy it fresh whenever wanted. Still, if placed in cold water, compressed yeast may be kept a few days in the ice-box, or may be buried in salt, and kept in a cool place.
Those who live at some distance from the grocery will probably find it more satisfactory to use dry yeast. This is made of a strong stock yeast, thickened with cornmeal and dried at a low temperature to prevent fermentation. The strength is somewhat variable, as the yeast plants gradually die, so, contrary to customary use, the supply of dry yeast should be renewed frequently in order to keep the bread results uniform. In using dry yeast the bread should always be started with a sponge; the dry cake should be dissolved in a small amount of tepid water, then added to the desired amount of lukewarm liquid, and enough flour to make a soft batter beaten in, about a cupful and a half to a pint of the liquid. When it has risen till light, the remaining flour and the other ingredients may be added. The bread recipes in this book have been standardized for compressed yeast, but dry yeast may be substituted if this method is used. When strictest economy must be practised, dry yeast is much less expensive when transformed into liquid yeast. In using this allow half a cupful to each pint of liquid to be used in making the bread.