Putrefactive' Putrefactive is a term used to describe the process of decomposition caused by bacteria or other microorganisms. It is the breakdown of organic matter by the action of putrefying bacteria, which produce foul-smelling substances and gases. Putrefaction is a natural process that occurs in all living things after death, and is an important part of the cycle of life. Putrefaction is also used to describe the process of decay in food, as well as the smell associated with it.