With more than 60 years’ experience of supplying freezer lines, IPCO’s systems combine efficient chilling technology with the exceptional conductivity of the company’s steel belt conveyors, explains Marko Leber, IPCO Global Product Manager.
Air blast freezing on a steel belt
IPCO is widely known as a world-leading manufacturer of steel belts for use in bake ovens, coolers, and other continuous processes, but the company is also a major supplier of complete food processing systems. The majority of these are based on steel belt technology, and for good reason. Perfectly flat and smooth, steel belts have no hidden gaps where bacteria could hide. They are inert and impermeable, don’t taint food or carry tastes. They are hard-wearing and long lasting and have unique thermal properties that make them ideal for applications such as freezing, where heat transfer and thermal conductivity is required.
IPCO supplied its first contact freezer in 1959, for ice-cream. This was followed shortly after by a brine steel belt contact freezer, used for fish fillets, juice and instant products. And today the company’s ranges include air blast steel belt freezers which use air for heat transfer. The combination of air blast freezing, and the outstanding conductivity of the steel belt offer a range of process benefits including reduced freezing times, consistently high product quality and low energy consumption. The smooth, joint-free surface enables the highest standards of hygiene to be maintained and means that products slide smoothly and cleanly from the end of the belt, minimising wastage, and breakages.
The use of blast-forced refrigerated air together with automatic belt defrosting and cleaning on each cycle provides the versatility and hygiene to handle everything from IQF freezing of whole fish, fish fillets, crabs, scallops, shrimps, and hamburger patties to freeze dried coffee, tea extract and baby food. Air blast systems are available in conventional form, where the chilled air is blown onto the product and under the belt, or with an impingement system, in which the chilled air is blasted onto the product and belt by means of air jets. Air blast freezers that incorporate impingement systems allow freezing times to be reduced by as much as 50%, which also means better product quality. Defrosting times are also reduced due to less ice formation on the air coils.
Air blast freezers that incorporate impingement systems allow freezing times to be reduced by as much as 50%, which also means better product quality
Freeze-dried instant coffee production
One of the fastest growing markets for IPCO’s freezing technology is instant coffee production. Recent years have seen all the world’s major producers install IPCO systems, reflecting the fact that freezing – with subsequent vacuum drying – has proved the optimum process for the efficient production of high-quality freeze-dried coffee. The inherent qualities of a steel belt lend themselves perfectly to this process. The hard, smooth, corrosion-resistant, and easy-to-clean surface not only ensures compliance with the strictest of hygiene regulations but also allows easy and clean discharge of the frozen product by means of a discharge knife. Freezing is carried out using cold air blasted over the product at high velocity to guarantee rapid and uniform heat transfer. An automated system of air flaps ensures quick and controlled defrosting of the plant.
The fact that steel belts can be supplied in an endless loop – in widths up to 2250 mm – means that production is both continuous and highly efficient. The steel belt conveyor itself is equipped with an automatic belt tensioning system and correct belt tracking is ensured by means of an automatic tracking system. In the next stage of the process, the frozen material is broken up, milled, and transported to the freeze-drying vessels where, by means of sublimation in a vacuum, the water component of the coffee mass is extracted. IPCO can supply all associated equipment including belt heating, product feeding and breaking, overflow collection and calibration of layer thickness. As is the case with all IPCO systems, the company can support installations through its global service network, with locally based teams supported by industry specialists.
