Heat represents the most efficient treatment to inactivate foodborne viruses and as a general rule, the higher the temperature, the higher and the faster the reduction in viral infectivity. Thermal inactivation kinetics data for foodborne enteric viruses and their surrogates in cell culture media are available. However, the impact of certain industrially applied thermal processes on viruses in complex matrices is not well described. This is owing to the difficulties in designing relevant laboratory-scale experiments, achieving recovery of spiked virus in subsequent tissue culture and natural microbial contamination problems linked to the matrix.
This presentation will focus on the work done in the frame of a collaborative project looking at the inactivation of virus surrogate and pathogen in extrusion cooking of petfood. Other processes will also be discussed, especially the effect of heat on viruses in low-water activity food matrices and the limitations of thermal processing for certain sensitive foods where non-thermal technologies need to be further explored to ensure the inactivation of viruses.