Biodiversity and dynamics of the bacterial community of packaged king scallop (Pecten maximus) meat during cold storage

Abstract

The microbial biodiversity and dynamics of king scallops meat and coral during cold storage (cold chain rupture: 1/3 storage time at 4 °C followed by 2/3 at 8 °C), was assessed by combining culture-dependant and -independent methods. Products were packaged as follows: aerobic, vacuum packed and 3 different CO2/N2 modified atmospheres and the impact of these conditions on the microbial communities was assessed. Results indicated that under air (current packaging condition), the dominant species corresponded to Brochothrix thermosphacta, Pseudomonas spp. and Shewanella spp. These species have regularly been associated in the literature with food (especially seafood), and product spoilage. Moellerella wisconsensis was the only species detected on VRBG medium, however, its impact on the food product is unclear. Packaging conditions influenced the ecosystem equilibrium and biodiversity. Except for day 8, the lowest counts for all studied flora were observed for modified atmosphere packaging (MAP) containing >80% CO2. Moreover, in these conditions, higher biodiversity by Temporal Temperature Gradient Gel Electrophoresis (TTGE) and the non-detection of specific flora (i.e. Pseudoalteromonas haloplanktis) were observed. At day 8, scallops packaged using these conditions were still acceptable from a sensorial point of view (odour), although the initial load of the king scallop was high (total psychrotrophic flora reached 5.5 log CFU/g).

Bacterial Community and Spoilage Profiles Shift in Response to Packaging in Yellow-Feather Broiler, a Highly Popular Meat in Asia

“…Recent finding has demonstrated that Acinetobacter was one of the dominant microbial species in foodservice environments, such as the pre-processing surface, storage room, and kitchen ( Stellato et al, 2015 ), and this may explain why high abundance of Acinetobacter was observed in control samples. Consistent with the finding in this study, little or no abundance of Acinetobacter was also identified in meat and aquatic products under aerobic and CO 2 /N 2 modified atmospheres during cold storage in previous studies ( Coton et al, 2013 ; Holl et al, 2016 ). Conversely, Zhang et al (2012) found that Acinetobacter was always the dominant species in air-packaged broiler during storage.…”

Sterol and steroid catabolites from cholesterol produced by the psychrophile Pseudoalteromonas haloplanktis

“…The growth of P . haloplanktis in seafood is sensitive to high CO 2 concentrations rather than to anaerobic conditions as it was detected in the vacuum packed or in the high nitrogen packaging conditions …”

“…On the other hand, P . haloplanktis is considered a specific flora of packaged seafood during cold storage, since the initial load of total psychrotrophic flora in seafood is high (about 5.5 log CFU/g) . The growth of P .…”

“…[3] On the other hand, P. haloplanktis is considered a specific flora of packaged seafood during cold storage, since the initial load of total psychrotrophic flora in seafood is high (about 5.5 log CFU/g). [4] The growth of P. haloplanktis in seafood is sensitive to high CO 2 concentrations rather than to anaerobic conditions as it was detected in the vacuum packed or in the high nitrogen packaging conditions. [4] Recently, an enzyme of cholesterol metabolism studied in the Sterolibacterium denitrificans was reported to resemble the 3-ketosteroid-Δ 1 -dehydrogenase putatively identified in the P. haloplanktis genome, as a high amino acid sequence identity was found.…”

“…[4] The growth of P. haloplanktis in seafood is sensitive to high CO 2 concentrations rather than to anaerobic conditions as it was detected in the vacuum packed or in the high nitrogen packaging conditions. [4] Recently, an enzyme of cholesterol metabolism studied in the Sterolibacterium denitrificans was reported to resemble the 3-ketosteroid-Δ 1 -dehydrogenase putatively identified in the P. haloplanktis genome, as a high amino acid sequence identity was found. [5] The 3-ketosteroid-Δ 1 -dehydrogenase has been reported to be involved in oxic metabolism of steroids lacking the aliphatic side chain on the C-17 position (i.e.…”