Vacuum packing is a packaging process that preserves food for longer by creating a vacuum that removes the air before sealing, preventing the growth of micro-organisms. It’s important to remember that foods which usually require refrigeration/freezing must also be kept in the fridge/freezer once vacuum packed It is necessary to take adequate precautions when vacuum packing. Vacuum packing can increase the shelf-life of chilled foods, by limiting the growth of microorganisms that cause spoilage. However, pathogenic bacteria (which cause illness) may have the opportunity to reproduce and the changes they make to the food may not be detectable by sight or smell.
In particular, under certain circumstances, a bacterium called non-proteolytic Clostridium botulinum (Cl. botulinum) may grow in the absence of oxygen. This bacterium is able to grow and produce a harmful toxin at temperatures of 3°C and above. Foods contaminated with Cl. botulinum do not generally look, taste or smell any different from uncontaminated foods.
Special equipment (domestic vacuum sealers) is required for vacuum packing food at home. All vacuum packaged foods should be clearly labelled and dated to manage the preservation process.
Keep the following food safety guidelines in mind when vacuum packing food:
- Wash your hands before and during the vacuum packing process
- Try not to touch food with your bare hands
- Keep all utensils, bags, and work surfaces clean
- Label and date each package
- Remember that foods which require refrigeration/freezing ordinarily, must also be kept in the fridge/freezer once vacuum packed.
More information on Botulism can be found in this FAQ from Food Safety Authority of Ireland.