pumpernickel a wholegrain rye bread from Westphalia in Germany, it is also known as Schwarzbrot (which may refer to many other types of bread) because of the characteristic dark colour that results from the caramelization of the starch in the rye grain during the long, slow baking process. This lengthy, low-temperature cooking means it can be kept for a much longer time than can standard yeast-risen loaves and was well suited to the ups and downs of peasant life and subsistence agriculture. The dough is not started with a sourdough culture but rather ferments spontaneously during an extended first proof (of up to 20 hours).
