Zeroing in On Uniform Cooking
True two-zone uniform cooking in new Twin-Drum Spiral Oven.
Uniform cooking was a primary design goal when Heat and Control set out to develop its new Twin-Drum Spiral Oven.
“Processors have often complained that they need to overcook product when using conventional spiral ovens which direct heat across one side of the conveyor drum”, says James Padilla, Heat and Control’s Director of Product Development. “Because temperature is lower on one side of the belt than on the other, cook times must be prolonged to assure all products reach a safe core temperature. Unfortunately, this practice reduces yield and overall production output.”
Drawing on its experience with single-drum spiral ovens and its AirForce® impingement oven, Padilla says Heat and Control focused on creating an oven enclosure and conveyor that would balance air flow across the entire spiral conveyor drum. So, instead of housing both spiral drums in a single rectangular box, separate cylindrical enclosures were used for each drum. An air circulation fan is centered atop each enclosure and surrounded by thermal fluid heat transfer coils.
Heated air flows in a 360-degree pattern uniformly across the conveyor from all sides providing consistent temperature across the belt and from top to bottom.
“Temperature probe tests confirm cooking is virtually identical across the left, center, and right sides of the belt”, states Padilla. “This oven is capable of cooking up to 15,000 lbs./hr. of poultry products with complete uniformity in a relatively short time.”
Separate drum enclosures also provide independent two-zone cooking control.
“Steam, dry heat, or any combination of both are independently controlled in each enclosure”, notes Padilla, who further explains how the oven offers unprecedented versatility in cooking and development of unique product characteristics. “In other ovens that use one enclosure with a divider between the spiral conveyor drums,” Padilla adds, “heat and moisture seek equilibrium across the divider and create a single, compromised cooking zone. The Heat and Control oven vents exhaust from both drums through a central stack between the enclosures so cooking conditions never intermix between zones.”
Cleaning has also been simplified with the Twin-Drum Spiral Oven. The conveyor support framework also serves as piping for the clean-in-place system, providing sprays to wash even hard-to-reach areas. Cylindrical enclosures eliminate corners where debris can accumulate, and raise clear of their bases for 360-degree access to all internal parts. NP