Effect of Transport Packaging and Repackaging into Modified Atmosphere on Shelf Life and Quality of Thawed Atlantic Cod Loins

Abstract

Boxes of expanded polystyrene (EPS, with or without ice added), corrugated cardboard (CC, with or without ice added) and polypropylene (PP, gel-ice inside the lid) were used in a case study, for transport of cod loins. Shelf life and quality were analysed after repackaging into modified atmosphere by use of culture dependent microbial methods, analysis of bacterial 16S rRNA sequences, sensory descriptive analysis and analysis of volatile components. The CC boxes showed faster temperature reduction compared to the EPS boxes when no ice added. Still, the microbial shelf life did not differ between transport packaging materials, but adding ice resulted in prolonged microbial shelf life. The sensory shelf lives were similar between all the treatments of MAP, but indications of prolonged sensory shelf life for the CC boxes both with and without ice added, compared to the EPS without ice added, were found. The EPS with added ice compared to the EPS without ice added did also show indication of prolonged sensory shelf life. The PP box seemed to have similar quality preservation as the CC samples with added ice. At the end of shelf life at least two different bacteria genera were detected on the MAP products: Psychrobacter, Shewanella, Carnobacterium, Pseudomonas and/or Acinetobacter. Photobacterium was presented in only minor levels, probably related to inactivation because of freezing. Summarized, this study showed that transport packaging concepts of corrugated cardboard boxes and polypropylene boxes preserved quality equally well as the EPS boxes prior to repackaging and further storage in MAP.

Thawed and chilled Atlantic cod (Gadus morhua L.) from Greenland - Options for improved distribution

“…3; Table 3; Magnússon & Martinsdóttir, 1995;Roiha et al, 2017). However, a dominating microbiota, including Psychrobacter spp., as observed for batch B, was also previously reported (Hansen et al, 2015). The measured concentrations of Pseudomonas spp.…”

“…Frozen storage for less than one months extended shelf-life of chilled refreshed cod marginally whereas sensory shelf-life was extended 3-4 days in ice following frozen storage periods up to twelve months (Magnússon & Martinsdóttir, 1995;Vyncke, 1983). After frozen storage during one to 12 months at -20 °C to -28 °C, several studies with cod from Belgium, Iceland and Norway found sensory shelf-life of 7 -15 days in ice for refreshed cod in air (Hansen et al, 2015;Martinsdottir & Magnusson, 2001;Roiha et al, 2017;Vyncke, 1983). Fresh cod from CBA in Greenland had sensory shelf-life of 15 days in air (Sørensen et al, 2020).…”

“…Baltic Sea cod had sensory shelf-life extended from 11 -12 days at 1.6 °C for fresh MAP fish to more than 20 days at 1.6 °C for refreshed MAP cod, previously frozen at -21 °C during eight weeks (Guldager et al, 1998). For Barents Sea MAP (13 % CO 2 , 83 % O 2 ) refreshed cod, sensory shelf-life was 19 days at 0 °C after frozen storage at -23 °C for ten months (Hansen et al, 2015). Also for Barents Sea MAP (34 % CO 2 and 66 % N 2 ) refreshed cod Bøknaes et al (2002) found sensory shelf-life of 21 days at 2.1 -2.5 °C after frozen storage at -20 °C during six to twelve months.…”

High Oxygen Packaging of Atlantic Cod Fillets Inhibits Known Spoilage Organisms, but Sensory Quality Is Not Improved Due to the Growth of Carnobacterium/Carnobacteriaceae

“…To extend shelf life, the processing and storage conditions should be optimized to prevent the growth of spoilage organisms present in fish. A common packaging method of gutted cod and cod fillets is aerobic storage in expanded polystyrene (EPS) boxes supplemented with ice to ensure a low chilling temperature [16]. Single packaged cod fillets and fillet products are also sold vacuum packaged or modified atmosphere packaged (MAP).…”

“…Some food packaging also include high levels of O 2 , which has shown to reduce the formation of TMAO to TMA in fish [23,24,[26][27][28]. However, the bacteriota under high O 2 storage has only been described in a few studies [16,23,24]. Studies also show that a mixture of bacteria presented during storage with a dominance of Photobacterium and Psychrobacter, followed by Moritella, Carnobacterium, Shewanella, and Vibrio as potential spoilage bacteria [29], and Carnobacterium spp.…”