First see that there is a supply of boiling water. Then put the salt, sugar, and flour together in a mixing-bowl. Wash and peel the potato, and grate it quickly into the bowl, covering it now and then with the flour to prevent discoloring. As soon as the potato is all grated, pour in the boiling water and stir. It will form into a somewhat thick paste at once. Set it aside to cool. Then dissolve the yeast in a little cold water, add it, and set the mixture to rise in a temperature of 70° to 80° Fahr.
In a short time bubbles will begin to appear; these are carbonic acid, showing that the alcoholic stage of the fermentation has begun. In six or eight hours the whole will be a mass of yeast cells, which have grown in the nutrient liquid. It is then ready for use. It should be bottled in wide-mouthed glass or earthen jars, and kept in a cool place. It will remain good for two weeks. At the end of that time make a fresh supply.
Yeast is an organism—a microscopic form of plant life—which grows by a species of budding with great rapidity when it finds lodgment in material suitable for its food. The dissolved compressed yeast is like seed, which, when put into a fruitful soil, grows so long as sustenance lasts.
WATER BREAD
1 Pint of boiling water.
1 Tablespoon of sugar.
1 Teaspoon of salt.
1 Tablespoon of butter.
⅓ Cup of liquid yeast, or
⅕ of a two-cent cake of Fleischmann's yeast.
Enough sifted flour to make a stiff dough.
Put the sugar, salt, and butter with the boiling water into a mixing-bowl or bread-pan. Stir until the sugar is dissolved and the water lukewarm, then add the yeast (if compressed, it should be dissolved in a little water). Last, stir in the flour until a dough stiff enough to mold easily is made. Mold it for a minute or two to give it shape and to more thoroughly mix the ingredients, and then set it to rise in a room warm enough to be comfortable to live in—that is, having a temperature of 70° Fahr. It should remain in this temperature for eight hours. Cover it closely, that the top may not dry.
It is often convenient to let bread rise over night. There is no objection to this, provided the bread is mixed late in the evening, and baked early the next morning. Care must be taken, however, that the room in which it is left is warm enough to insure rising in the time given. On the other hand, if allowed to rise too long, or at too high a temperature, the fermentation is carried so far that an acid is produced, and the dough becomes sour.
Eight hours at 70° Fahr. is a good rule to keep in mind. During the time of raising the dough should double itself in bulk. If this does not happen, or it does not appear to have risen at all, either the yeast was not good, or the temperature was too low.
When the bread has risen sufficiently, cut it down, and knead it for five minutes on a bread-board, to distribute the gas and break the large bubbles, so that the bread may have an even grain; then shape it into a loaf, put it into an oiled baking-pan, and let it rise quickly in a warm place, until it again doubles itself. The amount of dough indicated in the rule will make one large loaf, or a medium-sized loaf and some biscuit. Multiply the rule by two if you want two loaves. Bake the bread in an oven which is hot at first, but gradually decreases in temperature, for an hour and a quarter. If you have an oven thermometer use it.[43]