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Summary: Textural deterioration is a severe problem in fish industry. In order to study the role of structural proteins in refrigerated grass carp, myofibrillar proteins and collagen degradation were investigated at different stages. Results revealed that connective tissues of fish muscle disintegrated from day 1, failing to hold muscle myotomes together, with a decrease of shear force. Meanwhile, collagen solubility increased from day 1 and degradation of nebulin was observed after 3 days, while there was no obvious change in the bands of myosin heavy chain and actin. Furthermore, Pearson coefficient analysis revealed that insoluble collagen (ISC) and nebulin were significantly correlated with shear force. Negative correlation was established between drip loss and contributing factors (ISC, titin and nebulin). All results suggested that textural loss of post‐mortem grass carp fillets was mainly mediated by the degradation of collagen and to a lesser extent by myofibrillar proteins at the early storage. [ABSTRACT FROM AUTHOR]

The popularity of preprocessed fresh fishery products such as fillets and peeled shrimps is growing in today s market due to their convenience for subsequent processing and cooking. However, fishery products are highly perishable because of the combined actions of biochemical reactions and microbial metabolism. Various methods have been proposed to address this problem. Among these methods, bio-based edible coating has been highlighted as a promising solution. This review updates and summarizes the recent literature on the application of coatings for the preservation of fishery products including the aspects of coating carriers, composite natural preservatives and coating methods, and a discussion of the protective effects based on microbial, physicochemical and sensorial evaluations. Moreover, some challenges and future research directions regarding optimization of formulas and exploration of mechanisms of coating are also discussed. Given consumer demand for fresh fishery products with long shelf life, edible coatings that are environmentally friendly and effective alternative will be used to extend the shelf life of fishery products. [ABSTRACT FROM AUTHOR]

Biphasic biocatalyses such as the hydrolysis of olive oil and the esterification of octanol with oleic acid were performed in a CO2/N2-switchable Pickering oil-in-water emulsion stabilized by silica nanoparticles hydrophobized in situ by a CO2/N2-switchable surfactant (N,N-dimethyldodecylamine). Compared with biphasic systems, the enzyme in the Pickering emulsions displays a higher reaction efficiency, and demulsification and recycling of the enzyme can be simply realized by bubbling with N2/CO2. Moreover, the recycled enzyme still possesses significant catalytic activity. [ABSTRACT FROM AUTHOR]

This experiment was conducted to evaluate the efficacy of application of acetic acid and ascorbic acid spray on the surface decontamination and shelf-life of silver carp fish at refrigerated temperature (40C) during 9 days of storage period. Silver carp is one of the most abundant freshwater fish species in the world. However, the rapid quality degradation soon after post-mortem makes them highly putrefactive while reducing the nutritional attributes. In this regard, our study aimed at applying organic acids to extend shelf-life of silver carp fish while investigating the quality attributes such as sensory, peroxide values, pH and microbial loads of the fish fillets during 9 days of refrigerated temperature storage (40C). Acetic acid and ascorbic acid are found to have strong antibacterial activities against different microorganisms. Fish fillets samples were treated with alone or in combination with acetic acid and ascorbic acid spray while keeping one group of fish fillets untreated. Total Viable Count (TVC) was found greater in the samples kept untreated and treated alone with acetic acid and ascorbic acid. However, fish fillets treated with acetic acid and ascorbic acid in combination were reported with lesser number of microbial counts. Moreover, Peroxide Value (PV) and pH were significantly lower in the sample treated with in combination of acetic acid and ascorbic acid. Sensory analysis revealed that fish fillets treated with combined treatment had better quality retention at the end of 9 days storage period. The findings suggest that the application of acetic acid and ascorbic acid alone or in different combination have the potential to decrease microbial loads while facilitating the shelf-life of fish fillets during 9 days of refrigerated temperature (4°C) storage period. [ABSTRACT FROM AUTHOR]

Summary: To accelerate fermentation and improve quality of fermented fish, the impact of fermentation at elevated temperature on physicochemical, microbiological and flavour characteristics, as well as biogenic amines (BAs) accumulation of low‐salt fermented fish was investigated. Results showed that increasing temperature at later stage significantly promoted the growth of lactic acid bacteria, retarded the reduction of yeast and increased the titratable acidity, while staphylococci and enterobacteriaceae were inhibited to higher extent when fermented at elevated temperature. BAs contents in samples fermented at 30 °C during later stage were lower than those in the group fermented at 25 °C for 28 days, and the lowest values were observed in the sample initially fermented at 25 °C for 10 days followed by fermentation at 30 °C for 18 days. Furthermore, fermentation at elevated temperature at later stage favoured the formation of desired volatile flavour compounds. Results suggested that fermentation at elevated temperature at later stage could reduce BAs accumulation and enhance quality attributes of low‐salt fermented fish. The impact of fermentation temperature on quality attributes of low‐salt fermented fish. [ABSTRACT FROM AUTHOR]

This study was designed to evaluate and compare the stability, antioxidant and anticancer activities of selenium nanoparticles (SeNPs) decorated with different molecular weight (MW) of chitosan (CS) (1500 Da, 48 kDa, 510 kDa). The size range of well‐dispersed SeNPs was effectively controlled by I− first and then coated with CS. The morphology, size and surface charge of generated SeNPs were characterised by several technologies. Fourier transform infrared spectroscopy was used to investigate the relationship between SeNPs and CS. SeNPs decorated with CS (510 kDa) can keep stable for more than 45 days. As observed from the results of a simple photometric system, the antioxidant activities of decorated SeNPs were enhanced compared to undecorated SeNPs. SeNPs coated with higher MW of CS (510 kDa) showed the strongest antioxidant activities. Moreover, the treatments of SeNPs decorated with CS inhibited the growth of HepG2 cells in a time‐ and dose‐dependent manner. The proposed results demonstrated the critical roles of the MW of CS on the stability, antioxidant and anticancer properties of CS‐coated SeNPs, which provided an important design cue for future applications of functional foods and additives. [ABSTRACT FROM AUTHOR]

The quality of freshwater fish is easy to deteriorate during postmortem storage, so it is necessary to find an effective method to extend the shelf life of fish fillets. The aim of this study is mainly to develop a novel bilayer active film with curcumin/nisin-loaded pectin nanoparticles (CZ-NPs) and evaluate its effect on the quality of fish fillets. The selected sensory, physicochemical (pH, color qualities, TVB-N, TBARS, biogenic amines, moisture state) and microbial properties (microbial enumeration and high-throughput sequencing) were analyzed to confirm the preservative mechanism of films on the fillets. During storage at 4 °C, better sensory evaluation feedback and lower total volatile base nitrogen in the film treated samples was observed when compared to the control samples. Additionally, CZ-NPs film effectively inhibited oxidation, with the final reductions of 1.04 mg MDA/kg flesh when compared to control. As suggested by low-field NMR and magnetic resonance imaging, film treated fillets presented higher water holding capacity by controlling transformation from immobilized to free water. Meanwhile, lower microbial enumerations were also recorded in the CZ-NPs film treated group, which was reduced by a range of 1.8–2.3 log CFU/g on day 10 when compared to control. High-throughput sequencing results showed that the Pseudomonas constituted the main spoilage bacteria of fillets, and CZ-NPs film contributed to the notably suppressed growth of Pseudomonas. As a result, CZ-NPs film showed a desirable application to extend the shelf life of refrigerated flesh, as an alternative for fishery product packaging and preservation. [Display omitted] • The novel bilayer film was an effective way for keeping high moisture food fresh. • Bilayer active film packaging endowed fillets better sensory attributes. • Bilayer active films retarded the water migration and lipid oxidation in fillets. • The accumulation of biogenic amines was inhibited after film packaging. • Bilayer active films favorably shifted the composition of microbiota in fillets. [ABSTRACT FROM AUTHOR]