Vacuum packing, also known as vacuum packaging, is a method of sealing the food in an air-tight container where-in the air is extracted out from it, before packing the food inside. Air contains microbes that are likely to spoil the food, therefore, vacuum packed food has longer shelf life, as the food is no more in contact with air.
Both flexible packing and rigid packing can be done with this method. Especially nuts, coffee, cereals and smoked meats are vacuum packed.
History of Vacuum Packing Food Preservation
Vacuum packing was initiated by the Dr.-Ing. Karl Busch and his wife Ayhan Busch. Both of them set up their company named Dr.-Ing. K. Busch GmbH Company in 1963 in Germany, that made the first vacuum pump. The pump was designed by the Dr. Busch in his house basement within a record time. He tested it and sold it in the commercial market.
That pump was a ‘Hukepack’ pump that could ideally be used for vacuum packing food. Since then, the era of vacuum packed food had started and many recognized vacuum packaging companies and equipment manufacturers are still using the dependable ‘Hukepack’ pumps.
Vacuum Packaging: The Process
The food stored in a vacuum environment i.e. in air-free or air-tight container, inhibits the growth of bacteria and other organisms and this is the basic principle of vacuum packing. In general, the food is kept in a container either a bottle, can, tin or even a plastic bag. Vacuum pumps and other vacuum packaging equipments are used to create a vacuum environment inside the container and the pack is sealed immediately.
There are different types of sealers that are used for sealing the container after extracting oxygen from the package. Here are the following:
- External sealers – these sealers use an attached bag to seal the food item by removing the air through a pipe. This equipment does everything externally through vacuum pump.
- Chamber sealers – Unlike external sealers, this equipment requires the container to be kept inside the machine. Here also, a bag is used to seal the product that is normally kept inside the machine with the lid of the machine closed. The air is extracted from the bag and the product is sealed. As soon as the bag is sealed, the internal temperature of the chamber returns to normal. The bag is removed by opening the lid of the machine. Generally, this equipment is applied for high-volume vacuum packing.
Vacuum Packing Food Preservation Method: Advantages and Disadvantages
Like every food preservation and storing methods, vacuum packing also has its advantages and disadvantages. Here are the following:
- This packaging method extends the shelf-life of the food by inhibiting the growth of micro-organisms from the food.
- Delicate food items can also be easily packed with this method such as salted snacks, and especially potato chips. Nitrogen gas is inserted inside the pack to puff it up and this prevents the crushing of chips.
- It prevents freezer burn. The vacuum packed food are not exposed to dry and cold freezer air, this prevents the food to burn in freezer.
- ‘Sous vide’ French cooking is a popular cooking technique that is only possible with vacuum packed foods. In this type of cooking, poaching is done by keeping the vacuum sealed bag containing food, in a hot water bath for at least 72 hours. This water bath allows the food to cook evenly from all sides and even from inside and also, the juices are retained inside the bag.
- Vacuum packed food remains fresh only until the seal is opened. Leftover food in the container does not have long shelf life.
- Usually anaerobic organisms grow in the oxygen free environment that may threaten the food safety. Therefore, vacuum packing alone is not suitable for foods. Foods need to be processed with other food -preserving techniques as well.