E-beam tech on oysters can reduce foodborne illness, says study

The scientists said the study, the full results of which will be published in Applied and Environmental Microbiology in June, was the first to quantify the reduction in infection risks of raw oysters contaminated with different levels of virus when pasteurized at FDA-approved doses.

They said it showed that if electron beam pasteurization was included as part of a comprehensive food safety plan to reduce illnesses from raw oysters, significant public health benefits and savings in medical and related expenses due to foodborne illness would be possible.

Texas A&M University graduate student Chandni Praveen, Texas A&M AgriLife Research scientist Dr Suresh Pillai and researchers from other agencies and institutions, studied how electron-beam pasteurization of raw oysters may reduce the possibility of food poisoning through virus.

Pillai, professor of microbiology and director of the National Center for Electron Beam Research at Texas A&M University, said: “A salient feature of e-beam pasteurization technology is that it uses commercial electricity to generate the ionizing radiation that inactivates the viruses." ​

E-beam background​

At the moment electron beam technology is not being used for commercial oysters sold in the US.

However, the FDA has approved the use of electron beam technology as a pathogen intervention strategy to control the naturally occurring Vibrio vulnificus bacterial pathogen in shellfish.

E-beam treatment has been muted for years with its potential irradiation use on spinach and lettuce​ significantly cutting virus-related foodborne illnesses, according to an earlier study.

Pillai claimed the potential was being stymied by regulatory hurdles, industry naivety and costly equipment​ in a 2011 interview with FoodProductionDaily.com.

Method effectiveness​

The researchers of the new study choose norovirus and the hepatitis A virus, as they are pathogenic threats to those consuming shellfish and oysters as they are a type of mollusk that’s commonly eaten raw.

Pillai said that the study showed if a serving size of 12 raw oysters were contaminated with 100 hepatitis A and human noroviruses, an e-beam dose of 5 kGy (kilograys) would achieve a 91% reduction of hepatitis A infection risks and a 26% reduction of norovirus infection risks.

The researchers said that non-thermal food processing technologies are needed to reduce these infection risks.

Agency role​

Other entities involved in the study included the US Department of Agriculture (USDA), the US Food and Drug Administration (FDA) and University of Texas School of Public Health-El Paso regional campus.

The FDA recently issued an updated guide​ to ensure that raw oysters, clams, mussels, and scallops in the US market are safe to eat.

The guide was developed by the Interstate Shellfish Sanitation Conference (ISSC) with FDA support.

It represents the agency’s current thinking on appropriate controls for safe and sanitary growing, harvesting, processing, and shipping of molluscan shellfish intended for human consumption