Characterization of volatile compounds in a fermented and dried fish product during cold storage.

The northern European production technique for dry-cured meat sausages was used to produce a sliceable, fermented, and dried fish product rich in omega-3 polyunsaturated fatty acids (PUFA). The fatty fish Atlantic salmon (Salmo salar), the lean fish saithe (Pollachius virens) (1:1, w/w), Lactobacillus sakei, and 4 different milk protein-based ingredients were used in the recipes. The changes in the volatile compounds during cold storage (+4 degrees C) of vacuum-packed dried sausages were studied by dynamic headspace gas chromatography-mass spectrometer (GC-MS). Of the 117 volatile compounds identified, alcohols, alkanes, esters, aldehydes, ketones, and compounds derived from amino acids were the most prevalent groups of volatiles. Thirty volatiles decreased and 17 increased significantly (P < 0.1) during storage for 15 wk. Despite the high content of PUFA, amino acid catabolism and ester synthesis led to larger changes in the composition of volatiles in the fish product than did lipid oxidation reactions. The milk-protein-based powders that were used to physically stabilize the fish oil did not affect the lipid oxidation compounds.