Quality of Fresh Atlantic Salmon (Salmo salar) Under Hyperbaric Storage at Low Temperature by Evaluation of Microbial and Physicochemical Quality Indicators

Atlantic salmon (Salmo salar) quality was evaluated by hyperbaric storage at low temperature (HS/LT; 40-60 MPa, 5-15 degrees C) and compared with control samples stored at the same storage temperatures (5-15 degrees C) and atmospheric pressure (AP). Results showed that HS/LT was efficient to slowdown spoilage microbial growth, with additional inactivation at 60 MPa/10 degrees C after 50 days. Contrarily, AP-5/10 degrees C samples exceeded the established limit after 15 days. Furthermore, the established limit of total volatile base-nitrogen was surpassed at 60 MPa/10 degrees C only after 30 days (contrarily to 6 days at AP/10 degrees C), but with stable trimethylamine-nitrogen content in the former. Formaldehyde and dimethylamine-nitrogen contents increased after 6 days of HS/LT, but only the former progressively increased until the 10th day, indicating a possible formation by the action of enzymatic activity, but also by other chemical reactions. Additionally, HS/LT slightly increased secondary product content from the lipid oxidation, although to a lower extent compared with AP (at the different storage temperatures). Concluding, HS/LT may represent an interesting methodology to control microbial activity and important physicochemical parameters (such as volatile amines, colour, and lipid oxidation) of Atlantic salmon muscle portions for 15-30 days, compared with 6 days for AP/5 degrees C (conventional refrigeration).