JBT announced the launch of the new updated version of its Stein TwinDrum PRoYIELD 600 Spiral Oven with double-impact airflow technology. This is designed to provide uniform cooking with consistent temperature distribution across the conveyer belt.

The PRoYIELD takes the original TwinDrum two-zone cooking system and improves airflow consistency across the machine, enabling customers to cook products at lower temperatures. The result is an estimated up to 7% increase in yield for roasted and cooked food products such as chicken wings and fillets, while at the same time helping achieve a 5% reduction in energy use, according to JBT. The company says it's also versatile to cook burgers and patties, breaded products, pork, croquettes, seafood and ready meals. 

Featuring patented double-impact airflow technology, the PRoYIELD ensures heat and color distribution over the products inside the oven, thanks to the addition of Computer Fluid Dynamics and an Air Equalizer.

By reducing the internal temperature variation across the TwinDrum’s conveyor belt from as high as 6°C to a little as 1°C, the PRoYIELD ensures consistent cooking and product color across products moving through the oven. The technology is designed to not only preserve product moisture and maximizes yield but also mitigate the risk of overcooking and unwanted weight loss. 

For food processors using industrial spiral ovens, achieving the most even, left-right temperature across a conveyor belt for poultry and other products has long been a challenge with temperature variations all-too common.

The problem has meant that to get the products closest to the center drum consistently fully cooked, those positioned toward the outer-edges faced the problem of overcooking. In the case of cooked chicken, as products in the conveyor belt´s inner side reached the necessary temperature range of 77°C-78°C to ensure food safety, those on the outer edges often experienced higher temperatures, ranging from 80°C-85°C, due to the variation of heat distribution.

Teddy Svensson, JBT’s lead engineer on the development of the PRoYIELD, says, “Getting an even temperature over the width of a conveyor belt is notoriously difficult and it had proven problematic for every machinery manufacturer working in the industry. With the design that we have on our TwinDrum oven, the air rotates around the inside of the machine and down the spiral. I started to investigate how to better deliver air to the inner side to get a more even heat distribution.”

By making some subtle changes, Svensson and his team managed to achieve that outcome. “We developed a new heat-load model and found that the temperature was significantly improved from the original design where we had 5-6°C variation from the left to the right side, we got it down to 1-2°C,” he explained.

The PRoYIELD not only avoids overcooking products, the reduction in the overall temperature variation means cooking takes place evenly across the whole of the oven, ensuring product weight and moisture is retained. The process also allows processors to save energy as there is no need to heat the oven to higher temperatures than necessary.

The spiral oven cooking technology used in the JBT TwinDrum PRoYIELD Spiral Oven builds on oven engineering by adding a uniform temperature and roasting capabilities via a two-zone spiral system. The TwinDrum spiral oven’s design enables processors to increase their processing yield compared to alternative ovens in the market, while at the same time ensuring consistent cooking of food items by uniformly distributing the hot air across the conveyer belt.

The new Stein TwinDrum PRoYIELD Spiral Oven can be integrated with other JBT products to form complete in-line processing solutions, including the Stein and alco coating & frying equipment as well as Frigoscandia range of chilling and freezing systems.

 The Stein TwinDrum PRoYIELD Spiral Oven can be tested at JBT's Food Technology Centre in Helsingborg in Sweden.