Omic and Biochemical Profiling of European Anchovy (Engraulis encrasicolus) Fillets Under Sub-Chilled Storage

Sensory, proximate composition, microbiological analyses and fatty acid profiling, combined with omic analyses, were employed to examine qualitative changes in the fillet of fresh European anchovies (Engraulis encrasicolus), caught in September of years 2020, 2021, and 2022 in the North Aegean Sea (Greece), and stored for 72 h in a salt-containing ice slurry (sub-chilled conditions). Sensorially, the quality of the whole fish decreased significantly (p < 0.05) at the end of the storage period. However, total microbial viable counts remained relatively stable (≤105 CFU), as did the proximate components of the fillet, as well as the fatty acid profile of the total fat, with the main differences noted only in the distribution of the DHA and EPA in the lipid classes. Histamine levels remained at trace levels during storage and, from the proteomic analysis of the 2021 sample, significant differences were observed only in actin α1a, out of 27 major muscle proteins examined. The 16S rRNA gene analysis indicated important inter-annual changes in the anchovy’s microbiota, with no obvious pattern regarding the presence or changes in relative abundance of genera with spoilage potential during the storage period. Overall, the results suggest that short-term sub-chilled storage preserves to a large extent the nutritional and biochemical integrity of the anchovy fillets.