The second rise is an extension of fermentation and is the final step before baking. From the moment the bulk dough is punched down and shaped, secondary fermentation actually begins. Secondary fermentation is also referred to as proofing or final proof. It is the period of time that follows shaping and precedes baking. The purpose of proofing is to obtain maximum dough development by allowing the shaped dough to relax and expand to produce an aerated piece of dough which, when baked, produces the desired shape and volume. During proofing, the structure of the final product is set.
You'll also hear proofing used to refer to the process of testing the yeast to see if it is still active. This is a technique which is different.
Proofing temperatures generally occur within a range of 22°C to 29°C (72°F to 85°F), depending upon the formula and final product. Commercial bakers have access to programmable equipment called "proofers" or "proofing cabinets," which allow for the ultimate control of such factors as temperature, time, and humidity. Those of us baking at home, tend to identify areas within our environment in which the temperature is naturally or easily controlled, and devise makeshift techniques to have an affect on humidity.
If the dough is proofed at an improper temperature, or if there are fluctuations in temperature during proofing, the following defects or faults may occur:
- the dough may become too cool, resulting in a final product that is small and compact, with a dense crumb structure
- the dough may form a skin, inhibiting expansion during proofing and baking, and causing a pale, dull, and thick crust
To prevent dough from drying out, oil the surface of your dough and/or cover it loosely with plastic wrap. A layer of dried out dough does not stretch well and will inhibit the dough from rising effectively.
The pan the bread loaf is to be baked in is where the final fermentation should take place. For better shape and crust with artisan breads, many bakers let the dough rise in a greased bowl first, and then transfer it into a banneton for the second and final rise.
The key decision in the bread making process is ascertain when the loaves are ready to bake: The important function is to bring the dough to about 80 or 90 percent – rather than double in bulk - of its finished size, with some exceptions. The rest of the rise is expected through oven spring or oven kick, when the dough is first placed in the hot oven, especially when making freestanding loaves such as rolls or baguettes.
PERFECT: When the dough is gently pressed with your index finger, it should disappear slowly but completely within 2 to 3 seconds.
UNDERPROOFED: For imprints that don't remain for that length of time show that the dough is underproofed.
OVERPROOFED: Imprints that don't disappear mean the dough in overproofed.