High pressure processing at ultra-low temperatures: Inactivation of foodborne bacterial pathogens and quality changes in frozen fish fillets

• Published in: Innovative Food Science & Emerging Technologies
• Main Author: Boziaris I.S., Parlapani F.F., Mireles DeWitt C.A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2021
• Subjects: Diseases; Fish; Image quality; Meats; Salmonella; % reductions; High-pressure processing; Listeria monocytogenes; Pink salmon; Quality; Quality change; Salmonella enterica; Sub-zero temperatures; Subzerotemperatures; Ultra low temperatures; Listeria; Elsevier Ltd
• Online Access: http://hdl.handle.net/11615/72069; https://doi.org/10.1016/j.ifset.2021.102811

High pressure processing (HPP) at ultra-low temperatures was conducted against Listeria monocytogenes and Salmonella enterica in frozen pink salmon fillets. Quality changes, such as drip loss, color and odor attributes were recorded in non-inoculated pollock, pink salmon and tuna fillets. Pressures at 250 and 400 MPa were applied from 0.5 to 10 min. Reductions up to 3.5 log cfu/g were recorded for the treatments performed at −32 °C, in contrast to −50 °C where the reductions were only up to 1.5 log cfu/g. Higher pressure did not cause higher reduction. It was apparent that the main factor contributing to the bacterial inactivation is the phase transition of ice structure from I to III, in contrast to transition from I to II. Drip loss was not higher than the expected with HPP at temperatures above 0 °C, while color changes were negligible. Finally, the odor evaluation did not exhibit considerable differences between untreated and treated samples. Industrial relevance: High pressure processing at ultra-low temperatures is a promising treatment for bacterial inactivation and retention of quality attributes of frozen fish. Treatment at 250 MPa for only 3 min at temperatures just below −22 °C, which is feasible and affordable, caused a more than 3-log reduction against Listeria monocytogenes and Salmonella enterica, without affecting considerably the quality properties. Thus, the application of low pressure and shorter processing times gives a great potential for industrial application for frozen fish or fish that wouldn't be undesirable to freeze before pressurization. © 2021 Elsevier Ltd