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Abstract: Aim: The spoilage potential of 28 bacterial strains isolated from spoiled raw yellowfin tuna was evaluated. Methods and Results: Bacterial species were inoculated in irradiated tuna matrix. Chemical changes, bacterial growth and sensory quality were monitored during aerobic storage at 8°C. Pseudomonas spp., Enterobacter spp. and Escherichia hermanii had no spoiling effect. Brochothrix thermosphacta and Carnobacterium divergens/maltaromaticum developed moderate unpleasant odours. Hafnia paralvei and Serratia spp. released strong off‐odours (pyrrolidine, sulphur/cabbage). No bacterial group (except H. paralvei) combined with Pseudomonas spp. deteriorated the sensory quality of tuna. When C. divergens/maltaromaticum was associated with H. paralvei or B. thermosphacta, the odour is close to the naturally contaminated tuna stored on the same conditions. The pH, total volatile basic nitrogen (TVBN) and trimethylamine (TMA) were not correlated with the spoilage. Conclusions: The bacterial species had a different impact on the sensory quality of the fish. The bacterial interactions lead to an enhancement or an inhibition of the spoilage potential and the bacterial growth. Significance and Impact of Study: The specific spoilage organism (SSO) appears to be an association of lactic acid bacteria (LAB) with Enterobacteriaceae or B. thermosphacta. Pseudomonas, often dominant at the sensory rejection time, is not a good quality indicator. [ABSTRACT FROM AUTHOR]

Aims: The effect of vacuum (VP - 4°C) and CO 2 /N 2 -atmosphere (MAP - 4°C) packaging on the quality of red drum fillets compared with whole gutted iced fish was investigated., Methods and Results: A metagenomic approach, bacterial enumeration and isolation, biochemical and sensory analyses were carried out. The organoleptic rejection of whole fish was observed at day 15 whereas VP and MAP fillets appeared unacceptable only after 29days. At these dates, total mesophilic counts reached 10 7 -10 8 CFU g -1 . According to Illumina MiSeq sequencing, Arthrobacter, Chryseobacterium, Brevibacterium, Staphylococcus and Kocuria were the main genera of the fresh red drum fillets. At the sensory rejection time, lactic acid bacteria (LAB), particularly Carnobacterium sp., dominated the microbiota of both types of packaging. The pH value of fresh samples was between 5.96 and 6.37 and did not vary greatly in all trials. Total volatile basic nitrogen (TVBN) and trimethylamine (TMA) concentrations were low and not represent reliable indicators of the spoilage, contrary to some biogenic amines (cadaverine, putrescine and tyramine)., Conclusion: Chilled packed fillets of red drum have an extended shelf-life compared to whole gutted iced fish. Overall, few differences in sensory and microbial quality were observed between the VP and MAP samples., Significance and Impact of the Study: Next-Generation Sequencing (NGS) provided data on the microbiota of a tropical fish., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Our objective was to compare fruit morphology, physico-chemistry and bioactive compounds content of the edible pulp of six Mammea americana accessions. The results showed that this fruit was rather big, weighing on average 600 to 1100g depending on the accession, and spherical to oblate-shaped. The pulp represented between 50 and 70% of the weight of the whole fruit. The pulp adhered only partially to the seeds in 5 of the 6 accessions studied, while the last one exhibited full adherence. The fresh pulp was acidic, sweet, succulent and crunchy. The fruits studied had a variety of qualities, providing various opportunities for post-harvest uses: fruit salads, nectar preparation, jams and jellies, or export. We have established for the first time the total phenolic compounds and total flavonoids contents in the pulp of mamey apple fruits. The pulp colour was highly correlated with total phenolic compounds and total carotenoids contents., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Alpinia species, used as ornamental plants and flavoring agents, are renowned for their therapeutic properties and their subsequent use in traditional medicines throughout the world. Alpinia zerumbet (Pers.) B.L.Burtt & R.M.Sm. is the most common Alpinia species encountered in Martinique. Several essential oils (EOs) obtained by hydrodistillation of A. zerumbet flowers collected in various locations on the island at different seasons were analysed to evaluate the influence of the collection period and area on the EOs' chemical compositions and to assess their bioactivity. A combination of GC-FID and GC/MS techniques was used to examine the volatile constituents, leading to the identification of a total of 71 components accounting for 97.8 - 99.3% of the respective total GC-FID areas: among them, nineteen compounds were characterized for the first time in A. zerumbet EOs. The antimicrobial activity of these EOs was assessed against eight bacterial, yeast and fungal strains and two multi-resistant strains: some significant bacteriostatic and fungistatic activities of A. zerumbet flower oils were evidenced. Finally, an interesting insecticidal activity of the flower EO was highlighted for the first time against Aedes aegypti., (© 2017 Wiley-VHCA AG, Zurich, Switzerland.)

Metagenomic, microbial, chemical and sensory analyses of Thunnus albacares from Martinique stored in ice (AIR - 0 °C), vacuum (VP - 4/8 °C) and modified atmosphere packaging (MAP - 4/8 °C) (70% CO2 - 30% O2) were carried out. The organoleptic rejection of AIR tuna was observed at day 13 when total bacterial counts equaled 10(6)-10(7) CFU g(-1). No extension of shelf-life was provided by VP and MAP. According to 16S rRNA gene sequence analyzed by Illumina MiSeq and PCR-TTGE, Rhodanobacter terrae was the main species of the freshly caught tuna. At the sensory rejection time, Brochothrix thermosphacta and Pseudomonas dominated the AIR products while B. thermosphacta alone or a mix of B. thermosphacta, Enterobacteriaceae and lactic acid bacteria (LAB) dominated the microbiota of MAP and VP products, respectively. The pH value remained stable in all trials, ranging from 5.77 to 5.97. Total volatile basic nitrogen (TVBN) and trimethylamine (TMA-N) concentrations were weak and not significantly different between batches. Lipid oxidation increased in the samples containing O2 (MAP > AIR). The initial concentration of histamine was high (75-78 mg kg(-1)) and stable up to 8 days but then significantly decreased in all trials to reach 25-30 mg kg(-1), probably due to the presence of histamine-decomposing bacteria., (Copyright © 2016 Elsevier Ltd. All rights reserved.)