Development of a high pressure processing inactivation model for hepatitis A virus

Area of Science:

• Food science
• Microbiology
• Public health

Background:

• Hepatitis A virus (HAV) poses a food safety risk, particularly in shellfish.
• High Pressure Processing (HPP) is a non-thermal method for microbial inactivation.
• Understanding HPP efficacy against HAV in different salinities is crucial for food safety.

Purpose of the Study:

• To determine the inactivation kinetics of HAV under various HPP conditions.
• To evaluate the suitability of Weibull and log-linear models for describing HAV inactivation.
• To validate the predictive capability of the log-linear model in a food matrix (oysters).

Main Methods:

• HAV was suspended in buffered media with 15 or 30 g/L salt and treated with HPP (300-500 MPa, 60-600 s).
• Inactivation data were fitted to Weibull and log-linear models.
• The log-linear model was validated using HAV-inoculated oyster homogenate at 15 or 30 g/L salinity.

Main Results:

• HPP significantly reduced HAV titers, with higher pressures and longer times yielding greater inactivation.
• Inactivation was more pronounced in lower salinity media.
• The log-linear model provided a better fit and interpolation capability compared to the Weibull model.
• The log-linear model accurately predicted HAV inactivation in oyster homogenate at pressures ≥375 MPa.

Conclusions:

• HPP is a viable technology for inactivating HAV in shellfish.
• The log-linear model offers a reliable tool for predicting HPP efficacy against HAV.
• Further research with reproducible data is needed to refine the model for broader application in shellfish processing.