A German bakery may call a loaf Vollkornbrot, whole-grain bread, only if at least 90 percent of its grain is whole grain. The rule is in the guidelines for bread and small baked goods of the Deutsches Lebensmittelbuch, the German Food Book. The guidelines are not law. The Bundestag’s research service describes them as having the character of objective expert opinions. They are written by a commission drawn in equal numbers from science, food inspection, consumers and the food industry.