It is characterized by an abnormal color, consistency, and water holding capacity, making the meat dry and unattractive to consumers.
A mutation point in the ryanodine receptor gene (RYR1) in pork,[1] associated to stress levels prior to slaughter are known to increase the incidence of PSE meat.
The malignant hyperthermia (MH) or porcine stress syndrome (PSS) are the terms used to refer to the state pigs are found before slaughter, which will result in PSE.
Subsequently, the myofibers will continue to lose water content as the meat is cooled and stored, leading to excessive drip loss.
These animals become easily stressed pre-slaughter, which leads to exaggerated glycolysis, an increase in body temperature, and higher production of lactic acid.
[3] Conditions behind the PSE poultry meat are believed to be the same as observed in pork; higher rates of glycolysis postmortem lead to a sudden pH drop, which in turn causes protein denaturation and a loss of functionality,[2] important factor to create meaty products, such as sausages.
[2] Transport is one of the most critical moments before slaughter, taking up most of the time of the process, and the incidence of PSE is related to the position of birds in the truck and the design of the lorry/truck.
In the swine industry, the RYR1 gene, which encodes the ryanodine receptor protein, RyR1, was found to influence the incidence of PSE meat conditions.
The RN- dominant allele increases the glycogen content of the muscle, resulting in lower ultimate pH, a phenomen known as 'acid meat' or the 'Hampshire effect'.
Poultry breeding companies can lower meat qualities issues, including PSE, by selecting for traits in addition to yield and efficiency, such as health and cardiovascular wellness in order to increase tolerance to stress.
In birds, improving environmental quality will help to eliminate wing flapping, vocalizations, and excessive movement as animals are transported from the farm into the abattoir, which can reduce PSE incidence.
As solutions, automatic loaders and unloaders may be useful for the poultry industry (although this topic is under debate due to high level of noise from those machines).
[2] During summer time or in hot countries, the truck design should be taken into consideration, and passive ventilation and water shower before leaving the farm can have a positive effect and reduce the occurrence of PSE by up to 66.3%, which can be done by costless modifications.
Its frequency is increased due to extremely stressful conditions during transport, resulting in glycogen depletion, and insufficient rest in lairage that would help build up reserves, i.e., DFD it is the result of a series of poor decisions in slaughterhouse management in regards to excessive number of animals transported, abattoir lines free and unused capacity, or lack of communication between the slaughterhouse and farmers (accidents, road blocks, mistiming) in order to prevent issues.