Praxair Inc. announced the successful commercialization of its fourth generation ColdFront ultra performance flighted tunnel freezers that are designed specifically for processing individually quick frozen (IQF) foods.

“There’s over 30 years of experience and knowledge built into this latest design of the flighted freezer,” explains Frank Martin, Praxair food refrigeration marketing manager. “We designed this freezer to maximize yield and production capacity, while keeping quality high and freezing costs low. The flighted freezer also meets the new USDA sanitary guidelines, so these new systems are not only very effective and efficient, but easy to thoroughly clean.”

This latest design is proven with successful installations at both liquid carbon dioxide (CO2) and liquid nitrogen (N2) customers throughout the United States. A number of customers upgraded from an earlier version of the flighted freezer, embracing the new technology. One of these customers is Raw Seafoods, which installed the latest flighted tunnel freezer using liquid nitrogen for its scallop processing operation.

“We’re exceedingly pleased with our freezer,” said Raw Seafoods President Jason Hutchens. “Because of the way it’s designed, we have found the freezer system to be especially easy to clean and maintain - we have tripled our production since getting our new freezer,” added Hutchens. “We have been able to do so while reducing the nitrogen consumption per pound of scallops.”

Yield is maximized through direct cryogen injection at the freezer tunnel entrance. Exposing product to cryogen as soon as it enters the freezer ensures a quick crust freezing. Short individual belt flights gently tumble foods for reduced fines and deliver even, quick freezing on all surfaces. Both raw and cooked foods can be frozen into excellent quality IQF products. A wider belt width results in shorter tunnel lengths, allowing processors to maximize throughput while conserving valuable floor space.

Accessibility, sanitary design and ease of cleaning and maintenance are characteristic of the new design. Inside the freezer serpentine belt systems with cold belt capabilities provide excellent product release. For complete accessibility during clean-up and maintenance, there are vertical doors on both sides of the freezer that swing out of the way to allow open access to the freezer interior. Product guides and scraper bars are also removable for cleaning and additional access. The user-friendly design allows the operator to see the entire interior floor of the freezer, making any debris easier to locate and remove during cleaning. Belt motors and drives are located outside the freezer for ease of maintenance and service.

Based on the desired outcome, customers may customize their production to meet changing demands, economic conditions, product supply and type of cryogen used. Equally effective with either liquid carbon dioxide or liquid nitrogen, customers can match the cryogen selection based on gases used in other areas of the plant. Praxair food laboratory analyses ensure properly sized equipment and recommend operational parameters to maximize product quality and meet production goals.

The Praxair® ColdFront™ ultra performance flighted freezer system is applicable for a wide variety of food products including most seafood, meat portions, diced foods, vegetables, berries, pizza toppings, processed foods, cheese and other similar items where individual, freeflowing frozen food pieces are required. For more information on ColdFront ultra performance flighted tunnel freezers, visit