MULTIVAC has launched its new SFP Light steam flushing system, set to enable the immediate vacuum packing of hot food without cooling it beforehand – a process said to save energy and extend the product’s shelf life.
Traditionally, hot food cannot be vacuum packed because a decrease in air pressure also brings down the boiling point of water. MULTIVAC explains that if a machine created a negative pressure of 200 mbar, for example, the water inside the product would vapourise at 60 degrees centigrade, at which point it is no longer possible to reduce the pressure.
SFP Light aims to help caterers and kitchens vacuum pack hot food without waiting for it to cool down or losing time and energy to active cooling, and is available for MULTIVAC thermoforming packaging machines.
The machine uses a plastic film to form pack cavities, which are filled with food and sent to a hermetically enclosed sealing station. Here hot steam at a temperature of 180°C enters the station and the upper web is sealed to the formed film. When the steam cools into water, the pack contracts. It is also said that the heat kills bacteria on the surface of the food and extends its shelf life.
“Thanks to SFP Light, it is possible to pack hot products without any significant residual air pockets,” says Dominik Eberhard, product manager for Thermoforming Packaging Machines at MULTIVAC. “And all this without any vacuum source, which always has a limited effect due to the vapour pressure curve. There is also no danger of the products boiling or packs bursting, since there is no negative pressure in the product space.
“MULTIVAC has offered a SFP system for many years now for thermoforming packaging machines with high throughputs on an industrial scale. The new version is designed for smaller batch sizes in kitchens and catering companies. It is less complex as well as being space-saving and more cost-effective.”
Back in 2020, Sealed Air developed a soft vacuum packaging system with continuous flow with the intention of optimising product quality and improving sustainability for cheese processors. The solution reportedly combines a differential pressure vacuum with controlled pressure hot sealing to extract air from the pack, leaving the cheese exposed to atmospheric pressure as it is continuously packaged.
The company also hopes to achieve the Vegan Trademark for its CRYOVAC Darfresh vacuum skin packaging range after receiving the same credentials for its Sealappeal flexible packaging range.
A more recent development from MULTIVAC saw the launch of its R3 thermoforming machine for recyclable, mono-material packaging films.