Seasonal Variations in Skin Pigmentation and Flesh Quality of Atlantic Salmon (Salmo salar L.): Implications for Quality Management

Abstract

The external coloration of fish is a key driver in the consumer buying decision and is typically altered during sexual maturation in salmonids. Farmed Atlantic salmon (Salmo salar L.) exhibiting distinct phenotypes from the typical silver and nuptial colouration were described in terms of sexual development, flesh quality and skin pigment profiles. Reconditioning of skin colouration during storage was also tested (CIE[1976]L*a*b*) with the overall view of optimizing quality management. The intermediary phenotype never reflected significant deteriorations in flesh quality. It originated from a lack of purine pigments (guanine and hypoxanthine) revealing the carotenoid compounds dominated by the yellow-orange ß-carotene. The resulting distinctive lightness and yellowness were reduced by direct ice contact at a post-mortem stage. Storage conditions can be optimized to improve and standardize the coloration of whole-fish yielding superior flesh quality parameters. This would facilitate product quality grading during primary processing but also increase product acceptance and attractiveness.