ExamplesCALCULATION OF STERILIZING VALUESThis spreadsheet contains two usable functions:Function gValue calculates the residual temperature difference g = Th-T from the sterilizing value U (equivalent time at Th) and process parametersFunction Uvalue calculates the sterilizing value U (equivalent time at Th) from the residual temperature difference G and process parametersReference:Pham, Q.T., 1987, "Calculation of thermal process'lethality for conduction-heated canned foods". J. Food Sci. 52: 967-974.Example 1 of Pham's paperCalculate sterilizing value U from the following data:Symboldeg.Fdeg.CUnitsMeaningTi16071.1F or CInitial product temperatureTh230110.0F or CTemperature of heating mediumTc5010.0F or CTemperature of cooling mediumz168.9F or CTemperature change that will cause a tenfold change in the sterilization ratef5555minsTime for residual temperature difference to be reduced by a factor of 10, assuming logarithmic heating/coolingj22-Lag factor at centre for heating or cooling: (Th-T)/(Th-Ti) = j.10^*(time/f)t169169minsHeating timeResults of calculations:g0.1180.066F or CResidual temperature difference, Th-T, at the end of heatingU93.293.2minsSterilizing value at centre of canExample 2 of Pham's paperCalculate required temperature difference at end of heating, g = Th-T, from the following data:Symboldeg.Fdeg.CUnitsMeaningTi14060.0F or CInitial product temperatureTh240115.6F or CTemperature of heating mediumTc6015.6F or CTemperature of cooling mediumz1810.0F or CTemperature change that will cause a tenfold change in the sterilization ratef195195minsTime for residual temperature difference to be reduced by a factor of 10, assuming logarithmic heating/coolingj1.81.8-Lag factor at centre for heatingjc22-Lag factor at centre for coolingU16.216.2minsHeating timeResults of calculations:g12.296.83F or CResidual temperature difference, Th-T, at the end of heating

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