Microbial Risk Management: Clostridium Botulinum in Vacuum and Modified Atmosphere Packed (MAP) Chilled Foods

There has been a substantial increase in sales of vacuum and modified atmosphere packed (MAP) foods over the last decade or more.
The principal microbiological safety hazard for these foods is foodborne botulism, as presented by non-proteolytic Clostridium botulinum.
<p>Foodborne botulism is a severe but rare disease resulting from consumption of pre-formed botulinum neurotoxin. As little as 30ng of neurotoxin is sufficient to cause illness and even death. In view of the severity of botulism, regulators and industry work hard to ensure that it remains rare.
This has led to the production of various guidelines, recommendations and codes of practice with respect to the safe production of vacuum and MAP chilled foods.

<p>In 1992, the Advisory Committee on the Microbiological Safety of Food (ACMSF) published a report that included recommendations on the safe production of vacuum and MAP chilled foods with respect to C. botulinum, and the associated foodborne botulism hazard.
The ACMSF revised these recommendations in 1995. An industry code of practice was published in 1996 that included slightly different recommendations.
<p>In response to a request from the ACMSF in 2003, the Food Standards Agency produced in draft a small concise guidance document on the safe production of vacuum and MAP chilled foods with respect to C. botulinum.
The recommendations included in this document again differ slightly from those made by the ACMSF and the industry code of practice. The different recommendations relate to the '10 day rule' for foods with a short shelf-life where other specific controlling factors cannot be demonstrated.

<p>At the ACMSF meeting held in September 2003, the ACMSF agreed that the FSA concise document should go out to full public consultation.
The consultation period ended in August 2004. The most significant issue raised by the consultation surrounded a perceived change in the '10 day rule', and highlighted the differences between the ACMSF recommendations and the industry code of practice.
<p>At its meeting in December 2004, the ACMSF concluded that there was a need to examine recent scientific evidence before advising on the '10 day rule'.
The ACMSF asked the FSA to commission an independent review of relevant scientific evidence, with the findings to be presented at a future ACMSF meeting.

<p>The purpose of this project is to deliver an independent review of Clostridium botulinum in vacuum and MAP chilled foods for the Agency and ACMSF.