Final proof consists of the last stage of a bread's fermentation process, right before the dough goes into the oven. In some types of dough, most noticeably doughs made mostly from rye flour, it is a crucial stage, because it allows a further development of the dough. This process happens after the proofing, when the final shape of the dough is determined. It is a very short fermentation, during around twenty to thirty minutes, time in which the baker usually preheats the oven and the vessel in which the bread is going to be baked (preferably a heavy-bottom pan or dutch oven with a lid).