When fish are processed in trawlers at sea, the animals' heads, guts and skeletons all just go overboard. It's a lot of waste, and Norway's SINTEF research group is doing something about it. Working with commercial fishing company Nordic Wildfish, it's developed a system that puts everything but the bones to use.
The prototype system has been installed onboard an existing trawler, and starts by using a hydrolysis process to separate the bones from the rest of the fish waste – hydrolysis is the breakdown of a compound due to a reaction with water.
After the bones are discarded, what's left is described as a "soup" to which enzymes are added. The addition of those enzymes allows oils, proteins and amino acids to be extracted, which could subsequently find use in animal feed or even human food.
According to Nordic Wildfish, the entire process takes place aboard the trawler, which just entered service two months ago. The technology has so far mainly been used in the processing of whitefish such as cod, pollock and haddock. Down the road, their bones may also be processed to obtain calcium.
"Commonly it is only the fillets that are processed to become food," says Ana Karina Carvajal, Research Manager at SINTEF Fisheries and Aquaculture. "This is not sustainable food production. As we approach 2050, the demand for food on this planet will increase by as much as 70 percent due to high levels of population growth. The industry must make it its goal to utilize the entire fish."