Figure 1.

An overview of the three different parts (A–C) of the presented study. (A): Identification and collection of isolates. Cod fillets from three different plants were collected and stored at 3 °C in EPS boxes (air) for 6 (Plant 2 and 3) or 9 days (Plant 1). Fillets from Plant 1 were also frozen/thawed and stored in EPS boxes (air) and vacuum packaged for 9 days. Bacterial colonies were collected from agar plates at arrival (day 1) or after storage. The bacterial colonies were identified by partial 16S rRNA gene sequencing. (B): Growth screening of potential spoilage isolates. The growth of selected isolates from part (A) at 6 different atmospheres was tested on cod agar in trays. The total viable counts were registered after 21 days at 4 °C. (C): Storage experiment. Fresh fillets from Plant 3 were vacuum packaged (from commercial production) and packaged specific designed for the study by use of vacuum, and modified atmosphere (MAP) containing 60% CO₂/40% N₂ and 60% CO₂/40% O₂, all stored at 2 °C for up to 15 days. In addition, half of the packages were subjected to a short freezing process (40 min at −30 °C) before thawed and stored the same way as for the fresh fillets. Samples for TVC and bacteriota were collected after 1, 5, 8, 13 and 15 days, while samples for sensory- and volatile component (VOC) analysis were collected after 8 and 13 days. All fish samples used were of wild matured cod stored live in net pens for about two to four weeks prior to slaughtering (mean weight 5 kg) and pre-rigor filleting.