Injured microorganisms occur during the food manufacturing and are critical in sterilization and preservation, possibly causing food spoilage and foodborne illness. With reference to nonlethal but microbiostatic stress treatment, the abilities of growth, stress response, and tolerance change with time of microbiocidal treatment. In comparison with untreated healthy cells, injured cells possess several physiological characteristics and different sites in the cell are damaged, depending upon the type of the stress. Cell injury are also induced differently by the kind of method of exposure of cells to a stress and several antonymous injury modes are introduced or proposed here. For the detection and enumeration of injured cells, slow type cultivation method and rapid type non-cultivation method are available. Conventional plate counting method in the former has been widely used and fluorescent techniques in combination with flow cytometry as a representative of the latter have recently been concerned.
