Unitherm rolls out express smoking process

Unitherm Food Systems has developed a healthier, faster and more sustainable process for industrial food smoking applications using infra-red cooking.

Chief executive and president of Unitherm David Howard told FoodProductionDaily that traditional smoking took a long time because smokeries ran at relatively low temperatures of 90 degrees Celsius.

“When you smoke something you are trying to create a Maillard reaction [which gives foods a golden brown appearance],” said Howard. “A traditional smokehouse is unable to create the Maillard reaction in a small amount of time.”

The system Unitherm has developed is able to run at temperatures of 200 degrees Celsius, he said. “So the Maillard reaction happens fast and that creates a flavour profile equal to wood smoke.”

Natural browning agents

The company uses natural browning agents, such as smoke that has been condensed into a liquid in combination with high temperature tunnels of infrared, impinged air, or flame.

Products are pre-cooked, then chilled and smoked or browned in-line.

The higher temperature used also made the process inherently safer from a microbiological standpoint, said Howard.

“It will kill bacteria on the surface, because infra-red only hits the surface. Within 60 seconds [of exposure] you get a three log reduction for Listeria monocytogenes.”

Extended shelf life

One of the spin-offs of the process was that it also extended the shelf-life of products, in some cases doubling it, he said. “If a product has a 60 day shelf life, this will make it 120 days.”

The system had dramatically increased smoking speeds, said Howard. “What took the client six hours we are doing in 60 seconds.”

The process had tremendous potential given the popularity of smoked foods across the world, he said. “In the US, 95% of all deli-meat is smoked, browned and pasteurised.”

In Europe, the market for smoked meats in Poland was also significant and Unitherm had targeted food processors in the region with its smoking technology. It was now looking to roll it out to a wider customer base in many other countries, said Howard.

Removes carcinogens

The technology also removes any carcinogens, such as soot, tar and ash, from the process, delivering a finished product that is a lot healthier than more traditionally produced foods, he said.

Unitherm commenced business in 1983 in the UK. Its initial focus was improving the quality of ready meals by attempting to deliver crisper, meals that had a similar golden brown, crisp appearance to more traditionally cooked food.

The company worked with manufacturers such as Hazlewood Food Group, as well as retailers such as Tesco and Sainsbury on private label ready meals.