With regards to the food industry, they can cause spoilage, prevent spoilage through fermentation, or can be the cause of human illness. Another type of microorganism, the bacterial viruses or bacteriophage , will be examined in a later section. Bacteria Bacteria are relatively simple single-celled organisms. There exists a bacterial system of taxonomy, or classification system, that is internationally recognized with family, genera and species divisions based on genetics.
Some bacteria have the ability to form resting cells known as endospores .
The spore forms in times of environmental stress, such as lack of nutrients and moisture needed for growth, and thus is a survival strategy. Spores have no metabolism and can withstand adverse conditions such as heat, disinfectants, and ultraviolet light. When the environment becomes favourable, the spore germinates and giving rise to a single vegetative bacterial cell. Some examples of spore-formers important to the food industry are members of Bacillus and Clostridium generas. Bacteria reproduce asexually by fission or simple division of the cell and its contents.