Characterization of Bacterial Microbiota in Tilapia Fillets Under Different Storage Temperatures

Abstract

This paper investigates the bacterial microbiota in tilapia fillets under cold (4 °C), iced (0 °C), and superchilled (–3 °C) storage conditions. At 4 °C, at least seven species/strains of Pseudomonas were detected in the fillets, five of which were dominant either at a certain stage or throughout the entire storage period. Shewanella was less dominant than Pseudomonas at 4 °C, while Serratia became dominant after 6 days storage at 4 °C. The microbiota in fillets stored at 0 and –3 °C were very similar and rarely changed during storage, yet differed greatly from the microbiota at 4 °C. Only two Pseudomonas species/strains grew at 0 and –3 °C, one of which was the most dominant. A Vibrionimonas sp. not found at 4 °C was found to be the second most dominant species at 0 and –3 °C. Shewanella and Psychrobacter were also present at 0 and –3 °C but were the minor genera. The most dominant strains at –3, 0, and 4 °C were separately isolated and subjected to full length 16S rDNA sequencing, which demonstrated that they were identical and were Pseudomonas fluorescens. The changes of the total bacterial count and TVBN value of the fillets inoculated with the isolated P. fluorescens were very similar to those of fillets with natural microbiota. This implies that P. fluorescens is the most important spoiler of tilapia fillets at –3, 0, or 4 °C. Practical Application This research shows that fewer species of bacteria survive at 0 and –3 °C than those at 4 °C, while among these bacteria, the most important spoiler is P. fluorescens. This may provide some clues to extend the shelf life of tilapia fillets by taking some inhibitory measures targeted at P. fluorescens in the future.

The microbial safety of fish and fish products: Recent advances in understanding its significance, contamination sources, and control strategies

“…The gene of choice has been 16S rRNA because of its mosaic structure and the availability of a growing database (Ringø et al., 2016). Duan, Zhou, Xiao, Miao, and Zhao (2019) utilized polymerase chain reaction (PCR) amplification of 16S rRNA coupled with denaturing gradient gel electrophoresis (DGGE) and identified the major spoilers of tilapia fillets during cold aerobic storage as Pseudomonas sp., Shewanella putrefaciens , and Psychrobacter sp. High‐throughput sequencing has been suggested to have a better quantification reliability than PCR–DGGE in identification of fish spoilage microbiota.…”

Study on Microbial Community Succession and Protein Hydrolysis of Donkey Meat during Refrigerated Storage Based on Illumina NOVA Sequencing Technology

“…After 7 days of storage, the content of TVB-N reached 18.32 mg/100 g, which was far above edible standards ( Maršićlučić et al, 2008 ). TVB-N with the extension of time maybe was caused by nitrogen-containing substances degradation, such as proteins into amines and ammonia substances, which caused by endogenous enzymes and bacteria ( Duan et al, 2019 ; Kulawik et al, 2013 ). At the early stage of storage, the content of TVB-N was 7.16 mg/100 g, different from that of pork and beef, which might be related to different meat varieties ( Cai et al, 2011 ; Li et al, 2019c ).…”

Nasopharyngeal Bacterial Microbiota Composition and SARS-CoV-2 IgG Antibody Maintenance in Asymptomatic/Paucisymptomatic Subjects

“…Factor2 was mainly characterized by both opportunistic (such as Aeromonas ) and environmental microbiota genera (such as Caldicellulosibacterium and Comamonas ). Factor3 included different genera representative of environmental microbiota ( Adams et al., 2015 ; Lai et al., 2017 ; Duan et al., 2019 ). In particular, this factor had the highest loading also on Vibrionimonas , which was the only genus that was found to be different between SARS-CoV-2 RNA-positive and RNA-negative subjects after univariate analysis.…”