“This is a very effective solution, both for us and for our clients,” says Specialist Quality Consultant at Drammen Kjøkken KF, Knut-Are Midtun.Previously, food was produced according to the “cook and serve” method, which had to be delivered every day.
"When we cryogenically cool the hot food we produce, it can be kept for up to three weeks before being consumed. Now, we are ahead of ourselves and deliver food for three and four days on only two days per week. That means that the food can be heated up again, and is almost as good as if it were newly prepared. This is a good deal more efficient, and provides our clients with better service and products.”
Demonstrating the chilling process
Before Linde (former AGA) could deliver liquid nitrogen to Drammen, it went through a process of testing at its own freezing and chilling laboratory in Helsingborg, to which representatives of the municipality of Drammen were also invited.
“For both us and for the client, it is important to ensure the quality of decisions by carrying out real-life tests. Testing the chilling and freezing provides answers and reassurance for ongoing processes. By chilling rice pudding, the municipal representatives gained many answers, making the choice easier,” says Food Application Engineer at Linde (former AGA), Trond Kjærstad.
“Rapid freezing is essential for ensuring long shelf-life and the good quality of the product. This affects production planning and logistics to a high degree,” he says.
The tests turned out to be decisive for Drammen Kjøkken KF in terms of their choice of equipment to make use of the technology. The method is fast and hygienic. Cryogenic cooling works by spraying liquid nitrogen directly onto the food, cooling it down from +70–80°C to +1–4°C. Cabinet temperatures vary. As a rule, the process is started by reducing cabinet temperature to between -20°C and -40°C and then stabilising it at between -20°C and -25°C. The freezer cabinets cannot go down to temperatures lower than -80°C. The food is then packed with MAPAX®, a solution for packing in a modified atmosphere – or skin pack system – and labelled.
