Effect of the Combination of Vanillin and Chitosan Coating on the Microbial Diversity and Shelf-Life of Refrigerated Turbot (Scophthalmus maximus) Filets

Abstract

The effect of the combination of vanillin and chitosan (VC) coating on the microbiota composition and shelf-life of turbot (Scophthalmus maximus) filets during a 15day storage period at 4 ± 1 • day was investigated in this study. The control and coated fish samples were analyzed periodically for sensory and chemical attributes [total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), and pH] and the presence of dominant spoilage microbiota. The results suggested that the sensory and the chemical quality of turbot filets effectively improved after treatment with vanillin (final concentration 2 mg/ml) combined with 1% chitosan, and the shelf-life was prolonged for 6 to 7 days compared with the control group. Furthermore, high-throughput sequencing showed that Proteobacteria (52.2%) and Firmicutes (29.8%) were the dominant bacteria at the phylum level in fresh turbot filets, while Pseudomonadaceae (40.2%) and Lactobacillaceae (39.4%) were the dominant bacteria at the family level in deteriorated turbot filets. However, after VC treatment, the relative abundance of Pseudomonadaceae and Lactobacillaceae decreased significantly due to the growth inhibition of potential bacteria, specifically spoilage bacteria, along with the rich bacterial diversity at the end of storage. Therefore, our data indicated that VC treatment might be effective in decreasing bacteria-induced quality deterioration and in extending the shelf-life of refrigerated turbot filets.

Spoilage‐related microbiota in fish and crustaceans during storage: Research progress and future trends

“…Recent studies focused on fishery products preservation tended to adopt selective/differential culture to evaluate the antimicrobial effects of quality control techniques on different microbes (Table 1). Among different microbes, total psychrotrophic bacteria, Pseudomonas , Aeromonas , H 2 S‐producing bacteria, Enterobacteriaceae, LAB, and Photobacterium were the most frequently studied since they are common spoilage bacteria existed in fishery products (Cao, J., et al., 2020; Don et al., 2018; Huang et al., 2017; Kuuliala et al., 2018; Li, T., et al., 2020c; Macé et al., 2012; Silbande et al., 2018; Wang et al., 2019; Zhang, Y., et al., 2017). Nevertheless, phenotypic analysis is incompetent to give detailed and comprehensive information on microbial taxa composition, although it is inexpensive and requires less for professional skills.…”

“…PCA and PCoA similarity analysis are two main β‐diversity analyses that can characterize the microbiota variation between two groups by the distance between the two points in coordinate system. During the spoilage process of fishery products, points representing fresh and spoiled products are usually far away from each other due to the giant microbiota differences (Jia, Liu, et al., 2018; Jia, Liu, et al., 2019; Li, T., et al., 2020c). Treatment of quality control techniques often causes microbiota changes in spoiled products, which can also be visualized in PCA/PCoA plot.…”

“…COS dramatically decreased the relative abundance of Pseudomonas (day 6), while this inhibitory effect became less obvious when treated samples became sensory rejected (day 8). Besides, microbiota compositions of completely spoiled samples were also characterized and compared in some studies, either based on the same storage time (e.g., D–I or E–J) (Duan et al., 2020; Huang, Liu, Jia, Zhang, & Luo, 2018; Li, T., et al., 2020c; Zhuang et al., 2019) or the same spoilage degree (e.g., D–J) (Liu et al., 2017). Moreover, some studies (Huang et al., 2018; Jia, Liu, et al., 2018; Wang et al., 2014; Zhuang et al., 2019) characterized the microbiota composition before sensory rejection point and found out that some bacteria (e.g., Acinetobacter ) could be dominant before spoilage, although its predominance was finally occupied by SSOs.…”

“…According to all the examples above, the spoilage process of fishery products can be divided into two periods: the early period (from the beginning of storage to sensory rejection) and the late period (from sensory rejection to a completely spoiled stage). Microbiota composition of fish/crustacean flesh undergoes dramatic changes during the early period of storage, usually reflected as the decreased microbiota richness and diversity (Chaillou et al., 2015; Kuuliala et al., 2018; Li, T., et al., 2020c; Wang et al., 2019; Zhang et al., 2019; Zhuang et al., 2019; Zotta, Parente, Ianniello, De Filippis, & Ricciardi, 2019). With the increase of storage time, only a few taxa of bacteria become dominant in microbial communities and induce the final spoilage of fish and crustaceans (Chaillou et al., 2015; Kuuliala et al., 2018; Wang et al., 2019; Zhuang et al., 2019).…”

Shelf-Life Extension of Refrigerated Turbot (Scophthalmus maximus) by Using Weakly Acidic Electrolyzed Water and Active Coatings Containing Daphnetin Emulsions

“…The quality deterioration of fish after death results from the microbiological spoilage and biochemical reactions. The specifics spoilage organisms (SSOs) are considered to play a key role in the fish spoilage process (4). Weak acid electrolytic water (WAEW) is produced by the electrolysis of dilute sodium chloride or hydrochloric acid solution and exhibits strong antibacterial activities against SSOs, which has been considered as a new sanitizer (5).…”