RT Journal Article
SR Electronic
T1 Discussion of the Z-Value to Use in Calculating the F<sub>0</sub>-Value for High-temperature Sterilization Processes
JF PDA Journal of Pharmaceutical Science and Technology
JO PDA J Pharm Sci Technol
FD Parenteral Drug Association (PDA)
SP 51
OP 54
VO 50
IS 1
A1 PFLUG, I. J.
YR 1996
UL http://journal.pda.org/content/50/1/51.abstract
AB The appropriate z-value to use in integrating heat process time-temperature data in the temperature range of 120.0–140.0°C (248.0–284.0°F) is discussed. We conclude that for control of Clostridium botulinum there is little risk in extrapolating a public health F0-value for C. botulinum to temperatures in the 132.0–138.0°C (270.0–280.0°F) range using a z-value of 10.0°C (18.0°F). It would seem prudent, at this time, when extrapolating data to conditions in the 132.0–138.0°C (270.0–280.0°F) range, that as a starting point an F0-value of 3.0 minutes be used as the minimum public health process. A design z-value of 10.0°C (18.0°F) is appropriate for Clostridium sporogenes to temperatures of 140.0°C (284.0°F). To control thermophilic microorganisms such as Bacillus stearothermophilus and Bacillus coagulans with processes at temperatures from 120.0–140.0°C (248.0– 284.0°F), the effective z-value will be in the range of 7.0–8.0°C (12.6–14.4°F) instead of 10.0°C (18.0°F). This means that when we design and calculate processes at temperatures from 120.0–140.0°C (248.0–284.0°F), using a z-value of 10.0°C (18.0°F), the lethal effect against these organisms will be much larger than indicated by the F0-value of the process.