putrefaction

Putrefaction is a form of biological decomposition of organic matter characterized by the breakdown of proteins by microorganisms, producing foul-smelling products. It occurs mainly under anaerobic or low-oxygen conditions, when bacteria and some fungi break down tissues and other organic compounds. The process releases volatile compounds such as hydrogen sulfide, ammonia, putrescine, cadaverine, skatole, and various short-chain fatty acids, which together give the characteristic putrid odor. Gas production by these microbes can cause swelling and distention, and pigments produced during breakdown may alter coloration of tissues.

In living or recently dead matter, putrefaction is influenced by temperature, moisture, pH, substrate composition, oxygen availability, and the presence of insects. Higher temperatures generally accelerate microbial activity, while oxygen limitation fosters anaerobic bacteria such as clostridia and certain Gram-negative species. Putrefaction is part of the broader sequence of decomposition, which also includes autolysis (self-digestion by endogenous enzymes) and decay. It is distinct from later stages of decay that involve extensive liquefaction, skeletonization, or mineralization.

In forensic science, the extent and pattern of putrefaction can inform postmortem interval estimates under specific environmental conditions. In food safety and spoilage, putrefaction describes the microbial breakdown of protein-rich foods in anaerobic or poorly aerated environments, often accompanied by strong odors and potential health risks. Control measures include refrigeration, proper packaging, salting or curing, and sanitation to slow or inhibit anaerobic microbial growth.