Research looks at how omega-3 can spur sustainable aquaculture
The research project at Flinders University is primarily aimed at investigating whether Southern Bluefin Tuna can convert plant-based oils to omega-3 fatty acids.
The research, funded by the Australian Seafood Cooperative Research Centre, could lead to a more sustainable way of integrating healthy fish fats into human diets if it is successful.
Easy way has its flaws
Andrew Scholefield, lead researcher on the project, said that the simplest method to increase the quantity of omega-3 in fish is to introduce it into their diets; however, at least 10kg of sardines are required for a tuna to gain just one kilo in weight.
“While there are many health benefits in fish oil, getting it into the tuna diet drives up the harvest of fish in the wild, which is already at capacity. So we need to find an alternate way of feeding fish that are bred in aquaculture farms without taking more from the ocean,” he said.
To research this, Scholefield is using cells from the Southern Bluefin Tuna to test a theory that the marine animal can convert two main plant-based oils into healthy omega-3 fish oils.
He revealed that while most aquaculture nutrition trials are conducted on a large scale using a sizable quantity of live fish, he is cultivating the tuna cells in the lab to determine their growth rate, dietary uptake and how well they respond to certain diets.
Looking good for sardines
The results will be determined over the coming months, but Scholefield has revealed that preliminary findings look promising.
“Whenever an animal or human eats, the body converts that food into fat, protein or energy. We are looking to see whether tuna, when fed predominantly plant-based oils, can convert its diet to fish oil,” he said.
“Our goal is to retain as much human health benefit as we can from tuna while also using plant-based oils to make it more sustainable. It’s about finding a balance.”
He admitted that it will probably be impossible to ensure that tuna diets can be fully plant-based. “But if we can get some plant-based oils into their diets, we will move towards a more sustainable future [for fishing].”
