The concept of accumulated lethality has been used in relation to microwaves in order to validate the lethal effect of a previously established preserving treatment (Wang, Wig, Tang, & Hall berg, 2003). It has also been employed as a tool for assessing the effect of a conventional and a combined microwave-conventional pasteurization process on the nutritional and sensory quality of asparagus by calculating the C-value (Lau & Tang, 2002). However, to date, PU has still not been used with the aim of evaluating the
thermal load of various conventional and novel heating processes
to perform comparisons.