Abstract
Aims: The aim of this study was to determine if domestic cooking practices can reduce concentrations of norovirus (NoV) and F-specific RNA (FRNA) bacteriophage in experimentally contaminated mussels.
Methods and Results: Mussels (n = 600) contaminated with NoV and FRNA bacteriophage underwent four different cooking experiments performed in triplicate at similar to 70 degrees C and >90 degrees C. Concentrations of infectious FRNA bacteriophage (using a plaque assay) were compared with concentrations of FRNA bacteriophage and NoV determined using a standardised RT-qPCR. Initial concentrations of infectious FRNA bacteriophage (7.05 log(10) PFU g(-1)) in mussels were not significantly reduced in simmering water (similar to 70 degrees C); however, cooking at higher temperatures (>90 degrees C) reduced infectious FRNA bacteriophage to undetected levels within 3 min. Further investigation determined the time required for a 1-log reduction of infectious FRNA bacteriophage at 90 degrees C to be 42 s therefore a >3-log reduction in infectious virus can be obtained by heating mussel digestive tissue to 90 degrees C for 126 s.
Conclusions: Domestic cooking practices based on shell opening alone do not inactivate infectious virus in mussels, however, cooking mussels at high temperatures is effective to reduce infectious virus concentrations and the risk of illness in consumers.
Significance and Impact of the Study: The data will contribute towards evidence-based cooking recommendations for shellfish to provide a safe product for human consumption.
