Flour expired but no mold is generally not recommended to eat. Flour expired nutritional value will decline, but also easy to breed Aspergillus flavus, Trichoderma, Aspergillus oryzae and other microorganisms, so that the flour appeared lumpy, abnormal smell and other deterioration performance. At this time, although the flour does not appear mold, but has deteriorated, after eating may appear diarrhea, abdominal pain, vomiting, cyanosis and other toxic manifestations, some patients will also be serious liver damage or life-threatening. Therefore, when the flour has expired but has not undergone mold, it is usually not recommended for consumption. In daily life, flour needs to be stored in a dry, hot environment to help prolong the time it takes for deterioration to occur. In addition, avoid consuming flour within its shelf life if it has an odor, mold, insects, or lumps to avoid abdominal discomfort.