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BACKGROUND: Glycation is a green processing technology. Based on our previous studies, glycation with l‐arabinose and xylose was beneficial to enhance the texture properties of silver carp mince (SCM) gels. However, the possible enhancement mechanism remained unclear. Therefore, in this study, SCM gels with different types of reducing sugar (glucose, l‐arabinose, and xylose) were prepared based on our previous study. The possible mechanism of texture enhancement of SCM gels was analyzed by investigating the changes in water distribution, protein structures, and microstructure in the gel system. RESULTS: The glycation of l‐arabinose and xylose enhanced the hardness, cohesiveness, chewiness, and resilience of SCM gels. Hardness increased from 1883.04 (control group) to 3624.54 (l‐arabinose group) and 4348.18 (xylose group). Low‐field nuclear magnetic resonance (LF‐NMR) showed that glycation promoted the tight binding of immobilized water to proteins. Raman spectroscopic analysis showed that glycation increased the surface hydrophobicity and promoted the formation of disulfide bonds. Scanning electron microscopy (SEM) showed that glycation promoted the formation of uniform and dense three‐dimensional network structure in SCM gels. CONCLUSION: In summary, glycation enhanced the binding ability of immobilized water to proteins, improved the surface hydrophobicity, promoted the formation of disulfide bonds, and led to a more uniform and dense gel network structure of proteins, thus enhancing the texture properties of SCM gels. This research provided a theoretical basis for a better understanding of the mechanism of the effect of glycation on the quality of gel products and also provided technical support for the application of l‐arabinose and xylose in new functional gel foods. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The present study aimed to investigate the cryoprotective effect of epigallocatechin gallate (EGCG) replacing sucrose on surimi during frozen storage. Substitution or partial substitution of 0.1% EGCG for sucrose (1.5%) was added to surimi, and the surimi samples without and with commercial cryoprotectants (4% sucrose and 4% sorbitol) were used as the control group. RESULTS: The results obtained suggest that, with the increase in frozen storage time, the structural performance of surimi protein gradually weakened (e.g. the decrease in the surface hydrophobicity, the increase in the total sulfhydryl and solubility, and the protein myosin heavy chain bands became shallow) and surimi gel quality gradually deteriorated (e.g. the decrease in water‐holding capacity, gel strength and all texture profile attributes). However, compared with the other three group surimi samples during the frozen period, the surimi proteins with partial replacement of sucrose by EGCG had a higher total sulfhydryl group content and solubility of proteins, as well as lower surface hydrophobicity of protein, suggesting that the addition of EGCG as a partial substitute for sucrose can enhance the antifreeze ability of surimi. Meanwhile, the surimi gel with the partial replacement of sucrose by EGCG had a higher water retention capacity, gel strength and texture attributes (e.g. hardness, springiness, cohesiveness, chewiness, and resilience), indicating that the addition of EGCG as a partial substitute for sucrose can inhibit the deterioration of surimi gel quality. CONCLUSION: Overall, EGCG partially replacing sucrose can play an alternative cryoprotectant with a lower sweetness to prevent the quality of surimi from deteriorating. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Potentilla anserina L. is rich in various nutrients, active ingredients and unique flavor, comprising a natural nutrition and health food. However, its application in aquatic food has been rarely reported. Therefore, the effects of Potentilla anserina L. powder (PAP) on gel properties and volatile flavor profile of silver carp surimi were investigated. RESULTS: The gel strength and water‐holding capacity of the surimi gels were significantly improved (P < 0.05), and the whiteness and cooking loss of all the samples decreased slightly with the increase in PAP content. The addition of PAP shortened the relaxation time (T2) of the surimi gels and converted some of the free water into immobile or bound water, which resulted in a better immobilization of water in the surimi. Scanning electron microscopy images demonstrated that the network of surimi gels with PAP added was denser and had a smoother surface compared to the control. Volatile components (VCs) analysis showed that 33 VCs were identified in the surimi gel samples with different additions of PAP, among which aldehydes, alcohols and esters were the major VCs, accounting for more than 50% of the VCs in the surimi gels. PAP addition reduced the fishy and rancid flavor compounds in surimi gels, such as 1‐propanol, 1‐octen‐3‐ol, etc., and promoted the production of aldehydes, alcohols, esters and other flavor substances. CONCLUSION: These results of the present study provide theoretical support for the investigation and development of new nutrient‐health‐flavored surimi products. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Frozen tilapia fillet has become a leading aquatic product. High drip loss, dry and fibrous mouthfeel, and an unappealing appearance are its main problems. It was hypothesized that light salting could improve the quality, and that the preparation conditions would affect the storage stability of frozen tilapia fillets. RESULTS: The quality changes of lightly salted tilapia fillets were evaluated during frozen storage, and the underlying mechanisms were studied from the physicochemicaland microstructural perspectives. Though the salt content was 1.5% in all samples,the amount of ice crystals in frozen tissues decreased with the descending water content and freezing point (P < 0.05). No intracellular voids were observed in the samples prepared under proper salting conditions, and the myofibers were plump and smooth after freezing‐thawing, which contributed to the high water‐holding capacity of lightly salted fillets. After 28 days,the water‐binding capacity of the salted groups was 14.69%−18.62% higher than that of their unsalted counterparts (P < 0.05). The reduced protein solubility in the salted fillets was likely to have occurred because the solubilized and unfolded proteins interacted more easily during frozen storage. The oxidation degree of myofibrillar proteins was also affected by salting condition, and the fillets with less oxidized sulfhydryl groups maintained high springiness after 28 days of frozen storage. CONCLUSION: The salting condition of 9% NaCl solution for 1 h was recommended for the preparation of lightly salted fillets from freshwater fish, taking into account quality, processing efficiency, and storage stability. The enhanced water‐holding capacity and texture of lightly salted tilapia fillets were attributed to modified physicochemical and microstructural properties. These results could provide a scientific basis for the processing and storage of high‐quality, frozen, lightly salted fillets from freshwater fish. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Fish protein is a good source of amino acids and peptides with sensory properties. Theoretically, the type of protein affects the taste quality of the protein hydrolysates. To better use fish protein in the food ingredients industry, an in silico approach was adopted to evaluate the potential of fish protein to release taste‐active compounds. RESULTS: Six types of protein from seven commercial fishes were screened from the Uniprot knowledge base. The results showed that a remarkable number of umami fragments presented in myosin and parvalbumin (PB), such as glutamic acid (Glu), aspartic acid (Asp), and Asp‐ and Glu‐ containing peptides, whereas sweet amino acids and bitter peptides (e.g., Pro‐ and Gly‐ containing peptides) were mainly found in collagen (CGI) in all fish samples. After the in silico proteolysis by papain, a difference in the profile of taste‐active fragments was observed among the six types of proteins. Amino acids were the main hydrolysis products of these proteins, especially umami, sweet, and bitter amino acids, significantly contributing to the taste formation of protein hydrolysates. Besides, the myosin and CGI hydrolysates were abundant in taste active peptides both in types and quantities. CONCLUSION: Myosin is a promising protein source for producing umami fragments, and CGI seems to be a good precursor of sweet and bitter fragments. Different types of protein have an essential effect on the taste of protein hydrolysates. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND Although exogenous and endogenous formaldehyde in squid has led to severe health threat, an in‐depth study on natural edible scavengers for formaldehyde in squid is still lacking. RESULTS: Response surface methodology (RSM) combined with experimental verification approaches was applied to obtain an optimal 'recipe' to achieve formaldehyde removal rate of >85%: 6 mg mL−1 tea polyphenols, 20 mg mL−1 chitosan, 3:2 (v/v) tea polyphenols and chitosan, a pH value of 3 and 60 min treatment time. Apart from the capability of removing formaldehyde, the scavenger derived from natural food exhibited a significant preservation effect (extension of preservation time up to 40%) on squid during chilled storage, and was safe and environmentally friendly. Meanwhile, a synergetic effect of the two components on scavenging formaldehyde was unraveled by multimolecular infrared spectroscopy. CONCLUSION: An edible and bifunctional reagent composed of tea polyphenols and chitosan was developed for simultaneously removing artificially added or endogenous formaldehyde and for preservation of squid. The bifunctional coating shows promise as a formaldehyde scavenger and green preservative for aquatic products. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: Enzyme injection is vital for improving the sensory attributes and processing characteristics of meat products by enhancing proteolysis. However, studies regarding the appropriate dose addition for accelerating protein degradation in grass carp are minimal. This study aimed to investigate the impact of Flavourzyme® on the flavor quality and antioxidant activity of salted grass carp via brine injection and brining. Results: Flavourzyme was added at doses of 0, 5, 10, 20, and 30 leucine aminopeptidase units (LAPU) per kilogram of raw meat. The results indicated that adding Flavourzyme promoted proteolysis, which was reflected by the enhanced total free amino acid content (from 3.7414 g kg−1 to 4.9160 g kg−1 in the brining group and from 3.8039 g kg−1 to 5.4061 g kg−1 in the injection group) and a decrease in salt soluble and insoluble protein (P < 0.05). The antioxidant activity was improved, and the thiobarbituric acid reactive substance value in salted carp decreased due to the higher content of the protein hydrolysis product (P < 0.05). All sensory attributes were improved significantly, especially when using brine injection (P < 0.05). Brine injection was helpful to diffuse the Flavourzyme, resulting in stronger proteolysis. Conclusion: The appropriate Flavourzyme dose was 10 LAPU kg−1 in the injection group and 20 LAPU kg−1 in the brining group. Therefore, moderate Flavourzyme addition was excellent in improving sensory attributes and storage characteristics, whereas injection represented a novel method to obtain a similar fish meat quality in a shorter time and with less added Flavourzyme. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Among various cooking methods, steaming is favored by many because it can cause less damage to nutrient components in muscle, retain the inherent food flavor, and reduce the generation of harmful substances. Steaming conditions are closely related to fish flavor, fat and protein oxidation, and digestibility. RESULTS: The black carp steamed for 4 to 14 min was studied in this article based on sensory assessment, electronic tongue, free amino acids, adenosine triphosphate (ATP)‐related compounds, total nitrogen and non‐protein nitrogen to explore the effect of steaming time on the taste substances and protein degradation of pickled black carp. The experimental result showed that the meat steamed within 8 min tasted better, showing high tastiness. The sensory assessment score increased significantly to the maximum value of 82.33 at 6 min. The content of umami and sweet amino acids increased significantly to the maximum value of 1.6801 g kg–1 at 6 min. In the meantime, the IMP (inosine monophosphate) content was 1.9128 g kg–1, with its taste activity value (TAV) reaching 7.65, which proved that IMP affected the taste most. Furthermore, the total nitrogen content was 30.77 g kg–1, which meant protein degraded a great deal. Based on equivalent umami concentration (EUC) and its TAV, the meat tasted best at 6–8 min. The longer the steaming time, the faster the protein degradation and the more the flavor precursors. CONCLUSION: The black carp pickled products (with a weight of 20 g, with the size of 3 cm × 3 cm × 2 cm) is suggested to be steamed for 6 to 8 min. This conclusion provides a theoretical basis for its better taste quality. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The back cover image is based on the Original Article The impact of Flavourzyme on flavor, antioxidant activity and sensory attributes of salted grass carp by brine injection and brining by Shi Wenzheng et al., https://doi.org/10.1002/jsfa.11506. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION The taste of fish is highly dependent on the composition of free amino acids (FAAs) and nucleotides. The present study aimed to investigate the effect of long‐term frozen storage periods (−18 °C, up to 6 months) and thawing methods [water thawing (WT, 25 °C), air thawing (AT, 25 °C), and chilled air thawing (CAT, 4 °C)] on the taste quality of tilapia (Oreochromis niloticus) fillets.The results showed that increase in bitter FAAs of CAT samples was 150.57% at 6 months of storage, which was lower than that of AT and WT. Glycine was the most abundant FAA and CAT maintained the highest sweet FAAs (249.90 mg/100 g). Additionally, the inosine monophosphate (IMP) of CAT samples were 1.18 and 1.09 times higher than that of WT and AT, respectively, at a frozen period of 6 months. In particular, the increase in equivalent umami concentration (EUC) values ranged from 24.25% to 103.16% in the three groups during the first 2 months. Data from principal component analysis (PCA) and orthogonal partial least‐squares discrimination analysis (OPLS‐DA) indicated that the taste quality was highly correlated with high levels of FAAs, hypoxanthine inosine (HxR) and hypoxanthine (Hx) as the storage time progressed.In general, CAT is beneficial in maintaining the taste quality of tilapia fillets during frozen storage, and frozen durations for 2 months enhances the umami flavor. This study provides useful information for the preservation of frozen aquatic products during the storage and thawing, and enrich the theoretical knowledge of the flavor chemistry of fish products. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]