“Unique” single-step cook/pasteurization for shorter, cheaper processing

Developed by Swiss packaging specialists, Creative New Food (CNF) and German firm, International Packaging Systems (IPS), the continuous process known as MicroPast uses microwave technology to simultaneously cook raw food products and pasteurize them.

The novel technology allows a best-before date of 90 days to be achieved in a processing time of 10 minutes compared with two to three hours for pasteurization in a steam oven or autoclave.

Also MicroPast is said to improve product quality and cut operating costs. Significantly faster processing time is claimed to lead to a much reduced thermal load which increases the foods’ nutritional value and improves colouring and texture compared with other methods.

Cost savings​

Cost savings, based on an annual production output of 4m units, are estimated at18 cents per meal which would deliver annual savings of about €720,000, a CNF spokesperson told FoodProductionDaily.com.

“This cost reduction is achieved through lower cooking losses, lower logistical and personnel costs and also through the use of a continuous production method instead of batch operation,” ​she added.

As a one-step process, there is no need for pre-cooking lines for ingredients which cuts the footprint by 25 per cent compared with the autoclave technique.

Meals are guided in a closed plastic tray through a microwave tunnel, which cooks and pasteurizes them in a single step.

An opening in the upper film of the packaging operates as a valve with the water vapour acting as a heat conductor. “The result is an even temperature distribution, without cold or hot spots. The steam in the package provides counter pressure: There is no cell explosion and therefore, no drying out of food,”​ said the spokesperson.

After cooking, cold nitrogen gas is injected which is said to mean no squashing of food or removal of fluids.

At the end of the process, the pack is sealed by a high-tech label developed specifically for this purpose.

The process is said to be suitable particularly for temperature-sensitive foods such as vegetables, fish, seafood and poultry.

Microwave tunnel​

Components of the processing line depends on users’ requirements and how much existing equipment can be used. But the basics include equipment for deep drawing a container or destacking deep-drawn trays followed by product loading or filling, then positioning and sealing the upper film. The products are transported into the microwave tunnel, injected with gass and the MicroPast label applied.

Final steps are the cooling section and final packaging through to palletizing.

CNF opened recently its first MicroPast pilot line, featuring a microwave tunnel, gas injection and the application of a closure label, at its offices near Zurich. The company says the facility is open for demonstration and testing purposes.

The MicroPast system will be showcased at the IPA World Food Process Exhibition which takes place at the Villepinte showground, north of Paris between 17th to 21th October 2010.