The world population is increasing every year and it is foreseenthat the growth will continue the next several decades [1]. Thisleads to an increase in demand for high value proteins [2,3]. Existingprotein sources should therefore be used more sustainably in orderto ensure maximum utilization of protein for human consumption.This has driven scientists and industry to search for new environ-mentally sound and sustainable methods for improved utilizationof existing fish catches. By-products from fish offer high protein-containing raw material, and at present they are an underutilizedsource of high quality protein.