title: Relevance of calpain and calpastatin activity for texture in super-chilled and ice-stored Atlantic salmon (Salmo salar L.) fillets.
abstract: The aim of the present experiment was to measure the protease activities in ice-stored and super-chilled Atlantic salmon (Salmo salar) fillets, and the effect on texture. Pre-rigour fillets of Atlantic salmon were either super-chilled to a core temperature of -1.5°C or directly chilled on ice prior to 144h of ice storage. A significantly higher calpain activity was detected in the super-chilled fillets at 6h post-treatment compared to the ice-stored fillets and followed by a significant decrease below its initial level, while the calpastatin activity was significantly lower for the super-chilled fillets at all time points. The cathepsin B+L and B activities increased significantly with time post-treatment; however, no significant differences were observed at any time points between the two treatments. For the ice stored fillets, the cathepsin L activity decreased significantly from 6 to 24h post-treatment and thereafter increased significantly to 144h post-treatment. There was also a significantly lower cathepsin L activity in the super-chilled fillets at 0h post-treatment. No significant difference in breaking force was detected; however, a significant difference in maximum compression (Fmax) was detected at 24h post-treatment with lower Fmax in the super-chilled fillets. This experiment showed that super-chilling had a significant effect on the protease activities and the ATP degradation in salmon fillets. The observed difference in Fmax may be a result of these observed differences, and may indicate a softening of the super-chilled salmon muscle at 24h post-treatment.
authors.affiliation: Norwegian University of Life Sciences (UMB), Department of Animal- and Aquacultural Sciences (IHA), Post Box 5003, 1432 Aas, Norway. Electronic address: mari.gaarder@umb.no.
authors.forename: M Ø
authors.initials: MØ
authors.lastname: Gaarder
authors.affiliation: Norwegian University of Life Sciences (UMB), Department of Animal- and Aquacultural Sciences (IHA), Post Box 5003, 1432 Aas, Norway.
authors.forename: D
authors.initials: D
authors.lastname: Bahuaud
authors.affiliation: Nofima Mat AS, Osloveien 1, 1430 Aas, Norway.
authors.forename: E
authors.initials: E
authors.lastname: Veiseth-Kent
authors.affiliation: Nofima Marin AS, Osloveien 1, 1430 Aas, Norway.
authors.forename: T
authors.initials: T
authors.lastname: Mørkøre
authors.affiliation: Norwegian University of Life Sciences (UMB), Department of Animal- and Aquacultural Sciences (IHA), Post Box 5003, 1432 Aas, Norway.
authors.forename: M S
authors.initials: MS
authors.lastname: Thomassen
mesh_terms: D000818:Animals; D002135:Calcium-Binding Proteins / Q000737:chemistry*; D002154:Calpain / Q000737:chemistry*; D005511:Food Handling; D005519:Food Preservation; D007053:Ice; D020317:Salmo salar / Q000235:genetics*; D017747:Seafood / Q000032:analysis*; D013696:Temperature
chemical_list: D002135:Calcium-Binding Proteins; D007053:Ice; C033668:calpastatin; D002154:Calpain
keywords: ATP; Atlantic salmon; Calpains; Calpastatin; Cathepsins; Quality; Texture