Radiofrequency processing has raised
considerable interest in food industries
where the main applications involve
pasteurisation and sterilisation, roasting,
blanching, post-baking drying, thawing
and tempering. Since radiofrequency
treatments allow the rapid heating of food by
means of volumetric mechanisms, they are
generally regarded as particularly uniform.
However, few information is available on
the actual uniformity of the electromagnetic
field generated within the radiofrequency
processing plants. To this aim, a methodology
based on the image analysis of the extent of
dehydration in silica gel plates containing
cobalt chloride was developed
Investigations on the uniformity of radiofrequency heating processes are reported. Model system trials were conducted using image analysis of the extent of drying of silica gel plates containing an aqueous solution of cobalt chloride. Results showed that this is a useful technique for monitoring uniformity of radiofrequency fields in processing equipment and for evaluating effect of process modifications.
