There are no longer plenty more fish in the sea The potential of wrack macro-invertebrates as an alternative source of the marine origin omega-3 fatty acids: EPA and DHA

Abstract

Increasing population and affluence puts expanding pressure on global food security. Sustainably meeting future food demand requires novel and innovative food production techniques and technologies that are more efficient than those used today. Furthermore, the disconnect between the diets of people today and the diets for which we were naturally selected has numerous negative health effects. As such, future food must also be of high quality. This is particularly true of our omega-3 consumption relative to our omega-6. However, over recent years, rather than improving, the quantity of omega-3 in farmed fish produce, which is the most significant source of dietary omega-3 globally, has decreased. This is a result of overfishing reducing fish oil supply, creating a lower omega-3 content in the food of these farmed fish. Thus, finding an alternative omega-3 source that is more environmentally sustainable than fish oil is a top priority. This alternative must also be economically attractive and come with social benefits as the comprehensive adoption of any alternative relies on it improving the sustainability of all three of these pillars of society. Insects show much promise as a sustainable source of protein in food and feed and preliminary studies have identified wrack macro-invertebrates as having similar potential as a fish oil replacement. This research assesses the potential of this alternative by investigating the ease with which they could be cultured and their nutritional composition before crudely estimating their production cost and market value following this. The results suggest the biggest barrier to the use of wrack macro-invertebrates as a fish oil replacement is the inherent value of the seaweed substrate which prevents this from being economically viable. Furthermore, even if it were, higher returns of omega-3 would be obtained from the use of the seaweed as a feed ingredient directly.