Proofing (baking Technique)
Proofing (also called proving), as the term is used by professional bakers, is the final dough-rise step before baking, and refers to a specific rest period within the more generalized process known as fermentation. Fermentation is a step in creating yeast breads and baked goods where the yeast is allowed to leaven the dough.
Fermentation rest periods are not often explicitly named, and normally appear in recipes as "Allow dough to rise."
Proofing, as used in some cookbooks intended for home use, may refer to testing the viability of yeast. Dry yeast is mixed with a small amount of warm water and sugar, and if the yeast is viable, a layer of foam is developed by the action of the yeast. Typically, using US customary volume units, ¼ cup (≈ 59.1 mL) water at 105–115 °F (41–46 °C) and ½ teaspoon (≈ 2.5 mL) of sugar are used, or expressed differently, a sugar weight of about 3.5% of the water's weight. While this sugar may be sucrose or table sugar, instead it may be glucose or maltose, typically enzyme-derived from starch.
Proofing yeast may refer to the process of first dissolving yeast in warm water. Some believe this is a needed hydration step when using active dry yeast. Other bakers put active dry yeast directly into the bread dough undissolved. To hydrate the yeast, the weight of water required may be calculated: yeast weight x 4 = water weight. In one variant of the sponge technique known as poolish, proofing the yeast is the process step prior to feeding the yeast any carbohydrate.