Hepatitis A virus (HAV), feline calicivirus (FCV, a surrogate for non-culturable norovirus), and poliovirus (PV), suspended in buffered cell culture media, were treated with pressures ranging from 200 to 600 MPa at ambient temperature for between 30 and 600 s. HAV was inactivated by > 1-log10 tissue culture infectious dose 50% mL− 1 (TCID50 mL− 1) and > 2-log10 TCID50 mL− 1 after 600 s treatment with 300 and 400 MPa, respectively, and was undetectable (> 3.5-log10 TCID50 mL− 1 reduction) within 300 s treatment with 500 MPa. FCV was inactivated by 3.6-log10 TCID50 mL− 1 after 120 s treatment with 300 MPa, and was undetectable after 180 s treatment with 300 MPa. PV was the most resistant with little or no substantial reduction in titre after 300 s treatment with 600 MPa. The studies were designed to determine the efficacy of using high pressure to inactivate enteric viruses and generate inactivation data to assist in determining appropriate process criteria for safe shellfish production. The high pressure treatment of raw oysters has proved commercially successful, due in part to a marked increase in the product’s shelf life, yet little alteration of its organoleptic properties. Illnesses from human enteric viruses such as hepatitis A virus and norovirus have traditionally been associated with shellfish consumption, and for this reason, studies have examined the stability of enteric viruses under high pressure. However, kinetic data on enteric virus stability under pressure is needed by processors to better understand the response of viruses throughout the entire treatment time. The kinetic data obtained in this study may be useful for processors wishing to alter high pressure processing conditions to ensure a high quality product in terms of organoleptic and microbiological properties.
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