PROOFING DOUGH / RISING : During the process of making any yeast bread, as the yeasts take hold, and grow, and with the action of kneading, which builds up gluten strands in the dough, the dough will “rise.” The time required for the process of growing and rising will be different, depending on the ambient temperature and the sort of dough. If it is very cold, it will take a long while for the bread to rise properly.
One simple fix is to set the pan of dough into your oven with only the oven light on. Set the dough at the point furthest away from the light; even just that small light will get hot, and it could impede growth by killing off yeasts in the area closest to the heat source.
If your dough is a simple French or Italian style, made with flour, water, salt and yeast, the rising should take place quickly. If your dough is one heavy with sugar or fats, it could take a while longer as these will somewhat impede yeast growth. Either type is wonderful. The timing is the only difference.
YEAST, CAKE: Cake yeast comes wrapped in individual foil-wrapped squares. It is a “fresh” yeast and although it works faster than dry yeast, it is very perishable, and loses potency just a few weeks after being packaged. One cake usually equals one packet of dry yeast.
YEAST, ACTIVE DRY : One package generally equals about 2¼ teaspoons, or ¼ ounce. This is the kind of yeast called for in most bread recipes. It has replaced cake yeast almost entirely in stores. (I have not seen cake yeast since I was a child.) Active dry yeast should be proofed prior to using. See “Proofing Yeast”, below. Kept in the refrigerator, it will last well.
YEAST, INSTANT / Rapid Rise Yeast / Fast Rising Active Dry Yeast: All of these combinations of terms (Instant, Fast Rising, Rapid Rising) refer to “instant” yeasts. The instant yeast does not need to be “proofed” before using, and can be added in with the dry ingredients of the recipe.
YEAST STARTER : Also called a sponge, or the French term, “levain.” Generally this process is similar to proofing yeast, but done over a longer period. Some bread recipes call for a yeast starter, which is allowed to proof for the first rising period, and then proceeds with the recipe, adding in enough flour to form the dough. Some recipes call for a starter to be made and allowed to set for one to three days, before proceeding with the recipe.
The most famous yeast starter is one used for “sourdough” bread. This starter is allowed to ferment for many days before use. The fermenting period is what gives the famous soured flavor. The starter for sourdough breads is made to continue “feeding”, as the souring process continues. This means making more starter than is needed for one batch of bread. Enough starter is removed from the batch to use for your recipe, and to the remaining starter, more water, yeast and flour are added, and the fermenting process, already well underway, continues. Each batch as it is fed, is more soured, as more and more natural yeasts accumulate.
A true “levain” or Starter, is made just with water and flour, with the hope that naturally occurring yeasts in the air will make themselves at home in your starter. If you make yeast bread of any kind, on a somewhat regular basis, there are plenty of natural yeasts floating around in your environs. If you do not, it may get trickier to attract these wild yeasts. A good starter should smell strongly yeasty and a little sour. If it goes bad before attracting the yeasts, it may form mold or develop a very unpleasant odor.
Yeast Starter Dough