Unraveling Hepatitis E Virus susceptibility to heat treatment, pH reduction and drying in pork meat

Abstract

Foodborne Hepatitis E virus infection, linked mainly to pork consumption, is a significant public health issue in Europe. Despite the known risk of HEV contamination in pork, the effectiveness of meat processing methods in inactivating the virus is unclear, emphasizing the need for comprehensive investigations. This study examined the impact of common meat processing practices—heating, drying, and pH reduction—on inactivation of HEV in both suspension and pork pâté and sausages.

HEV suspensions were exposed to various temperatures (94 °C, 71 °C, 61 °C for 10 min; 73 °C, 100 °C for 20 min) and pH levels (pH 6.5, 6.1, 5.5 for 7 days at 7 °C and 20 °C). Pork pâtés were heated to temperatures of 68 °C, 72 °C, 80 °C, and 99 °C, while sausages were dried for up to 14 days and acidified to pH 4.1. HEV infectivity was assessed via immunostaining and methods evaluating HEV integrity.

Thermal treatment reduced HEV viral load variably, with complete inactivation only at 99 °C (>3.5 log reduction). Drying reduced viral RNA in sausages, but intact viral particles remained for up to 14 days. pH reduction showed minimal impact on viral particle integrity. Results in suspension were consistent with those in meat matrices.

This study is among the first to demonstrate in actual meat matrices that current meat processing methods might be insufficient for eliminating intact HEV particles in high-risk products like ready-to-eat pâté and dried sausages. The findings highlight the need for more effective HEV inactivation techniques and improved food safety measures to reduce the risk of foodborne HEV infections.