Because Clostridium botulinum is a bacterium that grows well in the absence of air. Commonly found in the environment, such as soil, water, and sea fish fresh food. When food is stored in oxygen-less conditions, such as in canned food in a sealed jar bacteria will flourish and produce toxins. Food that has been contaminated with the toxin may not show any abnormalities in the appearance,color, smell, and taste, however,does not mean that foods packaged in these containers must be infected and is toxic. Nowadays, canned food is a food product made popular because most people find easy to buy and inexpensive consumption. Moreover, it can be preserved for a long time.