Enhanced preservation of vacuum-packaged Atlantic salmon by hyperbaric storage at room temperature versus refrigeration

Hyperbaric storage at room temperature (HS/RT: 75 MPa/25 degrees C) of vacuum-packaged fresh Atlantic salmon (Salmo salar) loins was studied for 30 days and compared to atmospheric pressure at refrigerated temperatures (AP/5 degrees C, 30 days) and RT (AP/25 degrees C, 5 days). Most of the fatty acids were not affected by storage conditions, with only a slight decrease of docosahexaenoic acid (DHA) content (n-3 polyunsaturated fatty acid) for AP samples, reflected in the lower polyene index values obtained and higher oxidation extent. For HS, a lower lipid oxidation extension and a slower increase of myofibrillar fragmentation index values were observed, when compared to AP samples. The volatile profile was similar for the HS and fresh samples, with the HS samples retaining fresh-like alcohols and aldehydes components, which disappeared in AP samples, mainly in AP/25 degrees C samples. The volatile profile for AP samples (5 and 25 degrees C) revealed mostly spoilage-like compounds due to microbial activity. Drip loss increased progressively during the 30 days of storage under HS, while a slight decrease of water holding capacity after 5 days was observed, increasing further after 30 days. Regarding textural properties, only resilience was affected by HS, decreasing after 30 days. So, HS/RT could represent an interesting extended preservation methodology of fresh salmon loins, since allows retaining important physicochemical properties for at least 15 days, while refrigeration after 5 days showed already volatile spoilage-like compounds due to microbial activity. Furthermore, this methodology allows additional considerable energy savings when compared to refrigeration.

Automated summary

The study found that hyperbaric storage at room temperature had minimal impact on the fresh Atlantic salmon loins, retaining most important physicochemical properties. Compared to storage at room temperature or refrigeration, hyperbaric storage allows for considerable energy savings.