ORANGE FREEZING™ developed impingement technology for flat products as a way of delivering the same speed and quality as cryogenic freezing but at half the cost.
While speed and food safety have been key elements in the appeal of this technology, tangible quality improvements have also allowed some users to increase sales or command higher prices. One European frozen bread processor found that quality improvements were so dramatic that sales nearly doubled. A bacon processor found it was able to charge higher prices in the market because of the improved, softer texture and freshness.
“If you freeze food products very slowly, there’s time for the moisture to migrate,” explains Ayoub Lamri, one of the research and development engineers at ORANGE FREEZING™.
“When moisture can migrate and form larger crystals, those crystals don’t have as moist of a amouthfeel’ as when you freeze very quickly. If you leave time for the moisture to move around during freezing, the quality of the product changes.”
Faster freezing times result in smaller ice crystals, which means less cellular damage to food products. This means products are juicier, have better texture and exhibit less drip loss when thawed, according to Ayoub Lamri.
Thanks to its speed, impingement freezing actually results in less dehydration than other methods, because dehydration is a function of holding time within the freezer unit. For whitefish fillets, freezing in cold storage results in dehydration of 5to6percent. Airblast freezing in a static tunnel creates 4to5percent dehydration. In conventional in-line spiral freezers it ranges from 1.5to2percent, and in impingement freezers for flat products, the dehydration ranges from 0.6to1percent.
Impingement freezing uses thousands of high-velocity air jets to direct air at the top and bottom surfaces of a product. These jets of air blast away the boundary layer of air that holds heat around the product, resulting in freezing speeds that rival cryogenic. Among the potential applications of impingement technology are: p Meat products, e.g. hamburger patties. p Fish fillets, both raw and further processed. p Shrimp and shellfish. p Poultry, from raw parts to tenders, fillets and further processed products. p Bakery products and breads.
An application for a processor of fully cooked, 1.1-ounce (31grams) chilled chicken tenders, the infeed temperature was 80 Celcius and the target outfeed temperature (1°C. The afreezer’ permits a dwell time of 3.5minutes on a belt width of 49 inches (1250 mm) and belt load of 0.92pounds per square foot (4.5 kilos/m2). Dehydration is a relatively modest 2percent, while the capacity is all of 990pounds (450kilos) per hour in a single, 18-foot-long (5.5metres) module.
The Orange impingement freezer, a more flexible version of the Flat Product Freezer, is designed to fit into the same factories that otherwise use liquid nitrogen tunnel freezers and to freeze products as fast as liquid nitrogen. ORANGE FREEZING™ impingement technology is characterised by air jets that impinge directly on both sides of the flat product, removing the thermal boundary layer that surrounds it. The result is a heat transfer far better than conventional spiral freezers using mechanical refrigeration.
The Orange freezer can be applied to a wide range or processes, plants and configurations, accommodating seven different conveyor belt widths up to 6feet (1800 mm) or up to four lines of 1.5foot (450mm) width operating simultaneously.
The latter configuration allows for running four product lines independently or one wide sheet of product. For operations that require flexibility, a processor can run several products simultaneously or one wide sheet of product.
For freezing, the Orange freezer normally handles product thickness ranging up to two inches (50mm). For chilling applications, the unit handles thickness up to eight inches (200mm). Noting an advantage found by a processor of uncoated mozzarella cheese sticks, Ayoub Lamri says that a side benefit of the Orange freezer is that it can take the place of dryers in some operations, since jet drying is the first step of the process.
Despite the major boost in processing speed and quality, the Orange freezer has remained competitively priced, paying for itself generally within one to two years, notes Ayoub Lamri.
The technology is ideal for high-value products with high food safety risks. ORANGE FREEZING™ does the HACCP (Hazard Analysis and Critical Control Point) risk assessment and knows that these freezers are suitable for high-risk products because they’re based on a simple design.
“Ease of cleaning was a primary design factor taken into account from the outset, incorporating all curved surfaces and corners while offering high visibility.
These freezers are designed for access to everything.
In fact, if someone wanted to, they could drop an EURO inside somewhere, and you could find it in a matter of minutes.”