Unfortunately, it’s not that simple. Even in the absence of air, some types of bacteria can grow on food –Clostridium botulinum is one of these. We know this nasty bacterium multiplies, without air, even on chilled food stored at temperatures as low as 3°C. Because this bacterium produces a very harmful toxin that causes severe, and sometimes fatal, food poisoning known as botulism, it’s vital that appropriate controls are in place to make foods safe.
Vacuum packing and modified atmosphere packing are two processes that are used to inhibit the growth of bacteria and make food stay fresher for longer. While shopping, you may have noticed that some foods, such as bacon and smoked salmon, are vacuum packed. The packing process involves removing air from the packaging that surrounds the food and preventing its return by an airtight seal. Other foods, such as prepared salads that resemble an extended pillow, are packed in something known as a modified atmosphere. These foods have the air in the packet replaced with an inert mixture of gases after packing.
But because removing air is not enough to safely apply a shelf-life of more than 10 days at chill temperatures (3°C to 8°C), the two packing processes should be used in combination with one or more controlling factors. These controls include, among others, the level of acidity and the sodium chloride (salt) concentration of the food.
But, as with the application of any process, there are risks. So I welcome today’s launch of an online training course about vacuum packing and modified atmosphere packing. This food safety tool aims to give local authority food law enforcement officers who are responsible for food hygiene an enhanced understanding of these packing processes and the importance of the microbiological risks. The course complements the existing vacuum packed chilled foods guidance and factsheet for small businesses and enforcement officers, and supports the classroom-based version of the training available to enforcement officers.
The recent outbreak of E.coli on a Surrey farm, although not a food safety issue, reminds us of how seriously unwell people can become from bacteria. So I must emphasise that during the development of this tool, we have not forgotten the outcomes of the Pennington report that was published in March. This report on the public inquiry into the 2005 outbreak of E.coli O157 in Wales, highlighted concerns about the dual use of vacuum packing machinery for raw and ready-to-eat foods because of the risk of transferring harmful bacteria if the equipment is not cleaned properly. As part of our response to that lucid report, we are reviewing what further guidance is needed in this area, and this includes commissioning new research. Currently, there are no specific rules prohibiting the use of the same piece of vacuum packing equipment for raw and ready-to-eat foods.
I hope enforcement officers, as well as anyone else wanting to learn more about Clostridium botulinum and food safety, find the online course useful.
