Various factors influence the rate of rot.    External injuries: Ante-mortem or post-mortem injuries can accelerate rot because injured areas may be more susceptible to invasion by bacteria. [ref. needed] In alchemy, rot is the same as fermentation, in which a substance can rot or decompose undisturbed. In some cases, starting the process is facilitated by a small sample of the desired material to act as a “seed,” a technique similar to using a seed crystal in crystallization. [ref. needed] Light inhibits the process of putrefaction. Insects prefer to lay eggs in dark areas. As a result, areas exposed to light break down slowly compared to areas exposed to darkness. The first external sign of putrefaction is greenish discoloration of the skin of the anterior abdominal wall in the area of the right pelvic fossa.
In this area of the abdomen, the appendix, loaded with semi-solid intestinal contents and commensal intestinal bacteria, is found quite superficially. This greenish discoloration of the skin results from the formation of sulfhemoglobin, which is facilitated by commensal gut bacteria that invade tissues after death. This discoloration of the skin in the right iliac fossa occurs about 18 hours after death. In temperate climates, this greening can occur for the first time 2-3 days after death. The ambient temperature affects the speed of onset of putrefaction and its rate of progression. Two mechanisms are involved in decomposition: autolysis and rot.  Although decomposition begins shortly after death by autolysis, the macroscopic changes caused by decomposition become visible much later when putrefaction occurs. During this process, the body`s skin tissues rupture, releasing the blight gas. With the continuous process of rotting, the body eventually reaches a stage known as skeletonization, where only the skeleton remains. Body condition: A body with a higher percentage of fat and less lean body mass has a faster putrefactive rate because fat retains more heat and carries a greater amount of fluid into the tissues.  The approximate timing of events during the putrefactive phase is as follows: Certain substances such as carbolic acid, arsenic, strychnine and zinc chloride can be used to delay the putrefactive process in various ways, depending on their chemical composition.
Various factors affecting putrefaction are as follows: The visual result of infiltration of gaseous tissue is a remarkable swelling of the trunk and limbs. The increase in the internal pressure of the ever-increasing volume of gas further stresses, weakens and separates the tissues that restrict the gas. During rot, the skin tissues of the body eventually rupture and release the blight gas. While anaerobic bacteria continue to consume, digest and excrete tissue proteins, the breakdown of the body progresses to the skeletonizing stage. This continuous consumption also results in ethanol production by bacteria, which can make it difficult to determine blood alcohol levels during autopsies, especially in water-derived bodies.  Active disintegration is a stage in which putrefaction accelerates after flatulence. Post-mortem cleaning, in which putrefactive fluids are expelled from body orifices, is observable at this stage of decomposition. Detachment of hair or detachment of hair and black discoloration of cracked skin can be seen. The putrefactive process can be delayed by the use of carbolic acid, arsenic, strychnine and zinc chloride in various ways depending on their chemical composition. Available online and in four printed volumes, the encyclopedia is an indispensable reference for any practitioner in a medico-legal, medical, medical, legal, judicial or investigative field looking for easily accessible and authoritative overviews on a variety of topics.
The rate of rot increases with increasing temperature. The optimum temperature that supports the rotting process is 21 ° C to 38 ° C. The process stops below 0°C or above 48°C. In the swollen stage, some parts of the body, including organs and soft tissues, swell due to the accumulation of putrefactive gases or other decomposition products of the putrefactive process. It usually starts in the abdomen and then slowly affects other parts, including the face, breasts, and genitals.   Skin changes such as blisters and slips also occur at this stage. The sliding of the skin on the ends is called degloving. In addition, the phenomenon of marbling is also present in this phase, where the blood vessels on the skin are visible as greenish-black stripes, eventually leading to discoloration of the skin from green to black.  These postmortem changes are visible approximately 24 to 48 hours after death.
Bacterial digestion of cellular proteins weakens body tissues. As proteins are continually broken down into smaller components, bacteria excrete gases and organic compounds, such as the functional amines putrescine (from ornithine) and cadaverine (from lysine), which carry the harmful smell of rotten meat. Initially, the putrefactive gases are limited in the body cavities, but eventually diffuse through adjacent tissues and then into the circulatory system. Once in the blood vessels, putrid gases infiltrate and diffuse to other parts of the body and limbs. Advanced rot, also called black rot or subsequent decomposition, is a stage in which bones are exposed and the body takes on a “collapsed” appearance. Degradation-resistant tissues such as hair (although already depleted) and cartilage are spared until this stage.   Understanding the occurrence and evolution of post-mortem changes is essential for estimating the PMI.   The earlier a body is found, the more accurate the PMI estimate. Once a corpse is rotten, the PMI can only be given in approximate form, as many variables affect the rate of these changes.  The PMI estimate should not be based solely on a single post-mortem change. Instead, all post-mortem changes should be considered collectively to form an opinion about the time elapsed since death.
A reasonable forensic pathologist will never give an estimate of the precise “time of death,” but only a series of estimates of the “time since death.” Rot is the fifth stage of death, after Pallor mortis, Algor mortis, Rigor mortis and Livor mortis. This process refers to the post-mortem degradation of the body of an animal, such as a human. Overall, it can be thought of as the breakdown of proteins and the eventual breakdown of cohesion between tissues and the liquefaction of most organs. This is caused by the breakdown of organic matter through bacterial or fungal digestion, which causes the release of gases that enter the tissues of the body and leads to the deterioration of tissues and organs. The approximate time it takes to cause rot depends on several factors. Internal factors that affect the rate of rot include the age at which death occurred, the general structure and condition of the body, the cause of death, and external injuries that occur before or after death. External factors include ambient temperature, humidity and exposure to air, clothing, funeral factors and exposure to light. Fatal stiffness (postmortem stiffness) is the stiffening of cadaver muscles due to the depletion of adenosine triphosphate (ATP) after death with the subsequent accumulation of lactate in muscle tissue, resulting in an inability to loosen the actin-myosin bond. This post-mortem muscle change, which is approximately estimated, follows the initial phase of primary flaccidity of the muscles and, in turn, is followed by secondary flaccidity of the muscles, which coincides with the onset of putrefactive changes.