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Modelling holding time at a designated temperature on quality factor degradation.


To use the calculator add your data and press the submit button to obtain a prediction of the % residual value of the selected quality factor after heat treatment at a constant temperature.

Initial quality The default initial value has been set at 100 %.
Temperature (°C) at which D was determined e.g.72 °C
D value (seconds)* e.g. 319 seconds for IgA at 72 °C.
Duration of heat treatment (seconds) e.g. 15 seconds


* D is the time taken, at a given temperature, to reduce the concentration of the quality factor or biological activity by 90%. The D value should have been obtained or calculated at the same temperature used for thermal processing.

* I will add an explanatory note on the mathematics along with a table of D values and the ASP code for the calculator at a later time.






How to cite this article

Mullan, W.M.A. (2020) [On-line] Available from: Accessed: