New guide advises short shelf-life for vacuum and MAP foods

Although Clostridium botulinum ​food poisoning is very rare in the UK, its very serious nature means that any business engaged in producing VP or MAP foods must understand the risks associated with it, claims the Food Standards Agency (FSA).

The new FSA guidelines state that vacuum and MAP packed foods should have a short shelf-life, no greater than 10 days, unless the operator can show key control measures are in place.

The regulator said the guide is recommended for use by manufacturers and retailers and is aimed at assisting in the practical development of Hazard Analysis Critical Control Point (HACCP) for these foods.

The VP and MAP food guidance has taken four years to produce, following extensive consultation and analysis of a variety of data from the Advisory Committee on the Microbiological Safety of Food (ACMSF) and the industry, said the FSA.

"While we are not aware of any reported cases of Botulism (caused by C. botulinum) linked to chilled foods over the past 5 years, the high level of VP and ​MAP​ products on the market means we are keen to take preventative steps to stop any outbreaks occurring," ​an FSA spokesperson told FoodProductionDaily.com

"We also know from our conversations with Local Authorities and Environmental Health Officers that whilst many manufacturers observe good storage practices, some are simply not aware of the hazards,"​ she added.

Packaging technology​

The process of vacuum packaging removes air and prevents its return by an airtight seal. In the modified atmosphere or 'gas' packaging process, air is also removed and is replaced by a mixture of gases chosen from carbon dioxide, oxygen and nitrogen.

Although the techniques can protect food products from external contamination and increase the shelf-life, under certain circumstances C. botulinum​ may grow.

The bacterium thrives in atmospheres without air, leaving vacuum packed and MAP products more at risk. Some strains of C. botulinum​ are able to grow and produce toxin above 3° C.

Control measures​

The guidelines recommend that, in addition to maintenance of chill temperatures throughout the food chain, control factors such as heat treatment, food acidity, salt content, water activity and preservatives should be used to inhibit the growth and toxin production of C. botulinum.​

A decision tree to help the sector determine the shelf-life of VP/MAP products stored above 3° C is also included in the guidelines.

The FSA said the publication is designed to meet the needs of all levels of expertise within the raw and ready-to-eat vacuum packed or MAP chilled foods.

The FSA spokesperson added that while the guidance was produced primarily for a UK audience, it is equally applicable to a wider food manufacturing audience as MAP and vacuum packed processes are standard.