Texture measurement on gutted cod during storage in ice using a hand-held instrument

Fish muscle as food is to be seen as highly perishable. In unfrozen fish, freshness is considered the most important quality attribute. It is well known that there are several biochemical changes that can affect dramatically the texture of fish muscle. Immediately after death the fish texture is soft and elastic. In connection with rigor mortis the fish texture changes markedly. It becomes harder during rigor and after its resolution it becomes softer. This softness increases due to proteolysis during further storage at refrigerated conditions. Texture is a very important indicator for evaluating the quality of fish. Barroso et al. (1997) have recently reviewed mechanical methods in use for texture measurements on fresh fish. Further reviews on texture measurement performed on fish muscle were recently published underlining the importance of texture as quality attribute (Hyldig et al 2001, Coppes et al. 2002). The position along the fish can influence the results and was investigated by several authors (Sigurgis-ladottir et. al. 1999). Different methods have been compared for their ability to differentiate between recently killed salmon and salmon stored on ice for up to 24 days (Veland et al. 1999).