D-value (microbiology)
Encyclopedia
In microbiology
, D-value refers to decimal reduction time is the time required at a certain temperature to kill 90% of the organisms being studied. Thus after a colony is reduced by 1 D, only 10% of the original organisms remain. The population number has been reduced by one decimal place in the counting scheme. Generally, each lot of a sterilization-resistant organism is given a unique D-value. When referring to D values it is proper to give the temperature as a subscript to the D. For example, a hypothetical organism is reduced by 90% after exposure to temperatures of 300 degrees Fahrenheit for 2 minutes, thus the D-value would be written as D300F = 2 minutes. D-value determination is often carried out to measure a disinfectant's efficiency to reduce the number of microbes, present in a given environment.
Microbiology
Microbiology is the study of microorganisms, which are defined as any microscopic organism that comprises either a single cell , cell clusters or no cell at all . This includes eukaryotes, such as fungi and protists, and prokaryotes...
, D-value refers to decimal reduction time is the time required at a certain temperature to kill 90% of the organisms being studied. Thus after a colony is reduced by 1 D, only 10% of the original organisms remain. The population number has been reduced by one decimal place in the counting scheme. Generally, each lot of a sterilization-resistant organism is given a unique D-value. When referring to D values it is proper to give the temperature as a subscript to the D. For example, a hypothetical organism is reduced by 90% after exposure to temperatures of 300 degrees Fahrenheit for 2 minutes, thus the D-value would be written as D300F = 2 minutes. D-value determination is often carried out to measure a disinfectant's efficiency to reduce the number of microbes, present in a given environment.