Putrefaction
Putrefaction is one of seven stages in the decomposition of the body of a dead animal. It can be viewed, in broad terms, as the decomposition of proteins in a process that results in the eventual breakdown of cohesion between tissues and the liquefaction of most organs. It is caused by bacterial or fungal decomposition of organic matter and results in production of noxious odours.
Description
In thermodynamic terms, all organic tissue is a store of chemical energy, which, when not maintained by the constant biochemical maintenance of the living organism, begins to hydrolyse into amino acids, chemically simpler organic components. The breakdown of the proteins of a decomposing body is a spontaneous process, protein hydrolysis, which is accelerated as the anaerobic bacteria of the digestive tract consume, digest, and excrete the cellular proteins of the body.
The bacterial digestion of the cell proteins weakens the tissues of the body. As the proteins are continuously broken down to smaller components, the bacteria excrete gases and organic compounds, such as the functional-group amines putrescine and cadaverine, which carry the noxious odor of rotten flesh. Initially, the gases of putrefaction are constrained within the body cavities, but eventually diffuse through the adjacent tissues, and then into the circulatory system. Once in the blood vessels, the putrid gases infiltrate and diffuse to other parts of the body and the limbs.