Crisp bread, crispbread or hard bread (Swedish: knäckebröd, hårt bröd, hårdbröd, spisbröd, knäcke, Danish: knækbrød, Norwegian: knekkebrød, Finnish: näkkileipä, Estonian: näkileib, Icelandic: hrökkbrauð, Faroese: knekkbreyð, German: Knäckebrot or Knäcke, Low German: Knackbrood, Dutch: knäckebröd) is a flat and dry type of bread or cracker, containing mostly rye flour. Crisp bread is a staple food and was for a long time considered a poor man's diet. However, in recent years there has been renewed interest in crisp bread in the Nordic countries. Brands of crisp bread include: Vita wheat, Salada, Cruskits & Ryvita.
In the case of unleavenedcrisp bread, bubbles are introduced into the dough mechanically. Traditionally, this was done by mixing crushed ice into the dough, which then evaporated during baking. Today, the dough, which must contain a large amount of water, is cooled and mixed until bubbly.
Another method is to knead the dough under pressure in an extruder. The sudden drop in pressure then causes water to evaporate, creating bubbles in the dough.
Crisp bread is only baked for a few minutes, at temperatures usually between 200 and 250 °C.