Effect of salting process on the histological structure of salmon flesh

• Main Authors: Loison, Olivier, Jiang, Weijunlang, Venien, Annie, Gaubin, Oulyana, Cazevieille, Chantal, Astruc, Thierry
• Other Authors: Qualité des Produits Animaux (QuaPA), Institut National de la Recherche Agronomique (INRA), Institut des Neurosciences de Montpellier (INM), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM), Hôpital Saint Eloi
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2017
• Subjects: salting; salmon; processes; salage; chair de poisson; saumon; processus; [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition; Atlantic salmon; Salmo salar
• Online Access: https://hal.science/hal-01924390; https://hal.science/hal-01924390v1/document; https://hal.science/hal-01924390v1/file/Abstract-Loison%20et%20al_1.pdf

Atlantic Salmon , Salmo Salar, is composed of approximately 70% water, 19% protein, 10%lipid and 1% small nutrients (vitamins, glycogen, pigments .). Smoked salmon comes from theprocessing of fresh salmon: the fillets are removed from the fish, salted and then smoked. Saltingcan be carried out with dry salt or by brine injection. The objective of the study was to comparethe evolution of the cell structure and ultrastructure of the salmon muscle subjected to salting withdry salt and salting by brine injection.The experiment was carried out on 6 salmons. For each salmon, 1 fillet was salted with dry saltand the other fillet was additionally injected with brine. The fillets were smoked at lowtemperature (20-22 ° C). Samples were taken for histological analyzes (cryofixation, preparationof 10 μm thick histological sections, staining and observation by optical microscopy) andultrastructural analyzes (chemical fixation, dehydration, resin inclusion, ultrathin sections, stainingand observation by electron microscopy).The results show a decrease in the size of the extracellular spaces after injection of brine, which isprobably related to a swelling of the muscle cells that accumulate water. Dry salt salting, on theother hand, shows no difference in the extracellular size compared to the unsalted muscle.The salting substantially degrades the ultrastructure of the muscle with in particular a significantsolubilization of the Z-lines. Salting by injection of brine leads to swelling of the myofibrils andalmost complete solubilization of the Z lines.