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Calculator for determining the F or P values of thermal processes.This versatile calculator can calculate the cumulative value of most heat processes. Instructions on how to use the calculator can be obtained by clicking the icon. A "new data grid" is required for each new calculation. Before generating the data grid, the "start and end time" controls along with the "time interval" control should be used to define your input requirements. Then adjust the reference temperature and Zvalue and generate the data entry grid. Use the edit control to add your temperaturevalues. Remember to click the update link to enter your value! The software will then calculate the equivalent lethality at the reference temperature and using the Trapezoid rule, the cumulative lethality for your process. The F/P thermal process calculator can also be used to determine dry heat sterilisation, dry heat depyrogenation values, and whether requirements for pasteurization or guidelines for sous vide processing have been met provided the correct Tr and Z values have been used. The no of log cycles that a designated microbial population has been reduced by heating can be calculated by dividing the F value by the D value at Tr. A 12 log cycle reduction is required for the reduction of spores of Clostridium botulinium in 'commercially sterile' low acid canned foods. Six log reductions are required for most pasteurization processes. You can use the CSV import function to import your own data and the Z and Tr values can be modified to model F or P values using given time / temperature inputs.
Interested in downloading a Microsoft Excel
Spread sheet for doing F or P calculations?


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