Effect of Spatial Distribution, Storage, and Cooking Methods on the Volatile Profile of Atlantic Salmon (Salmo salar): Influence of Pre-Harvest Rearing Conditions, Sex and Presence of Skin.

Off-odor volatiles limit the acceptability of Atlantic salmon. This study investigated the effects of spatial distribution within the fillet, storage conditions, and cooking methods on the volatile profile of salmon and evaluated how pre-harvest rearing conditions, sex, and the presence of skin influence volatile compound formation during storage and cooking. Volatiles were classified as lipid-derived, protein-derived, and environmental contaminants. Spatial distribution within the fillet influenced volatile formation, with the head region exhibiting higher concentrations than the center and tail, reflecting differences in lipid distribution and precursor availability. During storage, fillets stored on ice generally exhibited higher volatile concentrations than samples frozen immediately, particularly for lipid-derived and environmental compounds, consistent with continued biochemical and microbial activity during chilled holding, whereas frozen storage preserved the biochemical state of the fillet. The magnitude of these differences depended on pre-harvest rearing conditions, the presence of skin, and harvest age. Cooking significantly increased volatile concentrations compared to raw fillets, with dry-heat methods, particularly baking, producing the highest levels, while boiling resulted in lower concentrations due to leaching into the cooking medium. Lower volatile formation was generally associated with cool-reared fish, male fillets, and muscle-only samples, while warm-reared, female, and skin-on samples exhibited greater volatile formation or retention, reflecting differences in precursor availability and tissue structure. These findings demonstrate that volatile formation in salmon is governed by the interaction between precursor accumulation during growth, spatial variability within the fillet, and transformation during post-harvest storage and cooking.