By Amy Lively, eHow Contributor

Proofing is a baking term that refers to the process of allowing dough to leaven, or rise, prior to baking. Proofing is caused by the fermentation of yeast in dough, which releases carbon dioxide that allows the dough to rise.

Proofer Function
A proofer, or a proof box, is a sealed space that provides a warm and moist environment for dough to allow it to rise before it bakes. The environment inside a proof box allows dough to rise more quickly than dough that is not proofed, as well as helps prevent dough from drying out.

Temperature Settings
Temperature settings on proofers typically range between 110 and 125 degrees, with humidity between 95 and 98 percent. Dough vary in their temperature and humidity needs, but if the proof box is too dry, the dough develops a skin and will not rise properly, while dough will be too soft and spread in a proof box that is too wet.

Making a Proofer
If a large commercial proofer is not available or necessary, it is possible to make a proofer. Putting a cup of hot water in a plastic box large enough to cover the dough and high enough to accommodate the dough's rise can simulate a proof box. Dough can also be put in an unheated microwave or oven, although a plastic proof box allows the baker to monitor the dough without opening the microwave or oven door.

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