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Abstract: Transglutaminase (TGase) is widely applied in the meat industry, and mixing of meat from various sources is an efficient way to enhance the quality of meat products. In this study, sensory scores, color, gel properties, water holding capacity and microstructure of mince mixtures, treated with 0.4% TGase, were determined to investigate the effect of TGase and mixing ratios (pork/fish, 10:0, 7:3, 5:5, 3:7, 0:10) on quality and gel properties of mince mixtures composed of pork and silver carp (Hypophthalmichthys molitrix). Results indicated that the mixture improved the sensory quality and gel properties of meat products compared to control group. The addition of TGase significantly (p < .05) increased the gel strength, especially at 7:3 ratio of pork and silver carp, in which gel strength reached its maximum and was 10.26%, 64.15% greater than pork with TGase and without TGase respectively, and water holding capacity were greater, and microstructure became more compact. The results suggest the synergetic interaction between proteins of pork and silver carp. TGase increased the interaction, especially for mixing proportion of 7:3 (pork/fish). Those results could be useful for the development of mixed and new meat products in the food industry. Practical applications: Pork and silver carp are two main meat in diet, and mince mixtures can improve the nutrition of meat product. TGase is usually used to enhance the texture and gel properties of meat in industry. The addition of TGase in pork/fish mince mixtures can not only improve the texture, but catalyze the synergetic interaction between proteins from different meat and further enhance gel properties of mice mixtures in a certain ratio. All of that will provide reference for meat processing and development of new meat product. [ABSTRACT FROM AUTHOR]

The effects of dry-curing with low concentrations of salt and sugar on the quality of rainbow trout (Oncorhynchus mykiss) fillets were studied over a 16-day storage period at 4°C. Physicochemical characteristics (total volatile base nitrogen (TVB-N), biogenic amines (BAs), ATP-related compounds and K value), microbial populations (total aerobic counts (TAC), H2S-producing bacteria, Pseudomonas, Aeromonas, and lactic acid bacteria) and sensory (SA) indicators were analyzed. Fish samples were subjected to the following treatments: untreated (control), dry-cured with 1.3% salt (T1), and dry-cured with 1.3% salt that also contained 0.9% sugar (T2). SA indicated that the sensory quality of the control, T1, and T2 was unacceptable after 8, 12, and 12 days of storage, respectively. Moreover, the cadaverine concentration of treated samples was significantly lower (P < 0.05) than the control after storing for 8 days. T1 and T2 were significantly higher (P < 0.05) than the control in inosine 5-monophosphate (IMP) content from the 2th to 10th day. Cadaverine, putrescine, hypoxanthine, and TAC were correlated significantly (P < 0.01) with SA, and these seemed to be reliable indicators of fish quality. The results indicated that curing treatments extended the shelf life of rainbow trout fillets, which could be exploited by processors. [ABSTRACT FROM AUTHOR]

To estimate biogenic amines and changes in quality of rainbow trout (Oncorhynchus mykiss) fillets at different temperatures, we determined the sensory attributes, total volatile basic nitrogen (TVB-N), total viable counts (TVC), and biogenic amines (BAs) of samples that were untreated (CK) or dry cured with 1.8% salt (T). There was no significant difference between CK and T samples in terms of TVB-N, TVC, and BAs. TVB-N and TVC increased significantly (P < 0.05) with storage time at 3, 9, and 15°C. Putrescine (PUT) and cadaverine (CAD) increased significantly (P < 0.05) at −3, 3, 9, and 15°C during storage. Histamine formed more easily when storage temperatures were higher. The kinetic models of sensory scores for TVB-N, TVC, PUT, CAD, and the sum of PUT and CAD (PUT+CAD) in T samples versus storage time and temperature were developed based on the Arrhenius equation. High regression coefficients (R2 > 0.9) indicated the acceptability of the kinetic model for predicting changes in the quality of the rainbow trout fillets. Relative errors between predicted and experimental values of TVB-N, TVC, and PUT+CAD were all within 10% except for TVB-N on day 6. The prediction model based on TVB-N, TVC, and PUT+CAD can be applied to evaluate changes in quality of rainbow trout fillets from −3 to 15°C (270 to 288 K). [ABSTRACT FROM AUTHOR]

In this work, we performed density functional calculations to investigate the adsorption and diffusion of hydrogen on Ni-loaded graphene and single layer graphene oxide (SLGO). We evaluated the feasibility of hydrogen spillover in the presence of Ni4 cluster and the role of oxygen-containing groups. Our calculations indicate that the hydrogen diffusion is difficult to take place on the Ni/graphene interface due to the stronger NiH bond strength. Further, the chemisorbed H atoms are also hard to diffuse freely on the graphene surface. For the SLGO surface, both hydroxyl and epoxide groups may not facilitate the hydrogen diffusion. Instead, they are readily attracted by the nearby Ni catalyst and hydrogenated to water molecules. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

We wanted to clarify whether gel properties can be affected by in vivo or in vitro myofibrillar protein oxidation and, thus, to provide relevant information and a scientific foundation for the processing of gel products. To accomplish this, we measured the changes in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), total disulfide (SS) content, surface hydrophobicity (So-ANS), carbonyl content, and gel texture and water-holding capacity (WHC) of isolated myofibrillar protein from bighead carp fillets during frozen storage and under different H 2 O 2 concentrations, which were used to represent in vivo and in vitro conditions, respectively. The results indicated that a certain range in content of disulfide crosslinks (0.91 mol/10 5 g protein) would promote gel hardness. Mild protein oxidation caused by a certain degree of frozen storage and hydroxyl radicals can promote gel texture and WHC. Based on those results, freezing bighead carp for a certain period can be used to produce gel products. [ABSTRACT FROM AUTHOR]

In this work, a novel nanosheets assembled porous fusiform Co 2 P 2 O 7 were successfully synthesized using a facile one-step hydrothermal method for ultrasensitive electrochemical sensing of As(III) in water. The unique porous structure and good dispersion facilitate a well-connected electron transfer path and provide numerous electroactive sites to bind with As(III). [Display omitted] • A novel nanosheets assembled porous fusiform Co 2 P 2 O 7 were successfully synthesized. • The porous fusiform Co 2 P 2 O 7 for the detection of As(III) by DPV was studied. • The proposed As(III) sensor exhibited a high sensitivity and low detection limit. • The reproducibility, stability and selectivity of the sensor are excellent. A facile and low-cost method was used to synthesize a novel nanosheets assembled porous fusiform Co 2 P 2 O 7 for ultrasensitive electrochemical sensing detection of As(III) in water. The porous fusiform Co 2 P 2 O 7 formed by small nanosheets exhibits a three-dimensional porous structure with a rough surface and good dispersion, facilitating a well-connected electron transfer path and providing numerous electroactive sites to bind with As(III). The proposed electrochemical sensor exhibited a high sensitivity of 91.04 µA µg/L cm−2 and a low detection limit of 0.087 µg/L towards As(III) in 0.1 M HAc-NaAc buffer (pH 5.0). Furthermore, it exhibited great potential for the electrochemical detection of As(III) in tap water. [ABSTRACT FROM AUTHOR]

In this review, the research progress of various kinds of nanomaterials for high performance of electrochemical HMI sensors were summarized in detail. The synthesis strategies, advantages, performance and challenges of the various nanomaterials for application in electrochemical HMI sensors are discussed. [Display omitted] • Deep insights into nanomaterials-based electrochemical HMI sensors were discussed. • Recent advances of electrochemical HMI sensing modified nanomaterials are reviewed. • The design ideas, innovations and merits of the modified materials were discussed. • Remaining challenges and prospects of the modified nanomaterials were presented. As one of the main pollutants, heavy metal ions can accumulate in the human body and cause a cascade of damage. Electrochemical sensors provide great prospects for tracing heavy metal ions because of their properties of high sensitivity, low detection limits and fast response. Electrode surface modification materials play a key role in enhancing the performance of electrochemical sensors. Herein, we summarize in detail the recent work on electrochemical sensors modified by carbon nanomaterials (graphene and its derivatives, carbon nanofibers and carbon nanotubes), metal nanomaterials (gold, silver, bismuth and iron), complexes (MOFs, ZIFs and MXenes) and their composites for the detection of heavy metal ions (mainly include Cd(II), Hg(II), Pb(II), As(III), Cu(II) and Zn(II)) in food and water. The synthetic strategies, mechanisms, innovations, advantages, challenges and prospects of various electrode modification nanomaterials for the detection of heavy metal ions in food and water are discussed. [ABSTRACT FROM AUTHOR]

In recent years, high voltage electrostatic field (HVEF) technology has been demonstrated to be a viable alternative to high-temperature treatments in processing for inhibiting microbial growth and maintaining post-thawing quality of foods. In this study, common carp ( Cyprinus carpio ) meat cubes were treated with HVEF, and compared to air-thawed and running tap water-thawed controls to investigate how HVEF affects common carp meat quality after thawing and low-temperature storage (4 °C). The results showed that thawing under − 6, − 12 kV HVEF and running tap water significantly decreased the thawing time by 30, 50 and 45 min, respectively, compared to air thawing control. In addition, − 12 kV HVEF treatment also reduced the moisture loss, which the initial drip loss of it was lower by 2.95% than CK. The initial total viable counts, Aeromonas , Pseudomonas , and lactic acid bacteria were 3.58, 3.15 2.88 and 3.25 log CFU/g in CK after thawing, respectively, which were higher than that in the cube thawed by − 12 kV HVEF (3.11, 2.93 2.71 and 2.91 log CFU/g). Additionally, − 12 kV HVEF treatment enhanced adenosine monophosphate deaminase (AMP-deaminase) activity, reduced acid phosphatase (ACP) activity and delayed the degradation of inosine monophosphate (IMP) to hypoxanthine (Hx). These results suggested that HVEF treatment could be useful in the thawing and storage of frozen common carp fish. Industrial relevance The study investigated the effects of high voltage electrostatic field (HVEF) thawing on the water-holding capacity, adenosine triphosphate degradation and microbial community changes of frozen common carp ( Cyprinus carpio ) cubes when stored at 4 °C. HVEF under − 12 kV was found to have positive influence on reducing the thawing time, maintaining water-holding capacity, decreasing the level of microbe, and delaying adenosine triphosphate (ATP) degradation. A potential application for HVEF in the thawing and storage of frozen aquatic product was highlighted in food industry. [ABSTRACT FROM AUTHOR]

The present study investigated the effect of cinnamon essential oil on the quality of vacuum-packaged common carp ( Cyprinus carpio ) fillets stored at 4 ± 1 °C in terms of sensory scores, physicochemical characteristics (total volatile basic nitrogen (TVB-N), biogenic amines, and color), and presence of spoilage microbiota. A total of 290,753 bacterial sequences and 162 different genera belonging to 14 phyla were observed by a high-throughput sequencing technique targeting the V3–V4 region of 16S rDNA, which showed a more comprehensive estimate of microbial diversity in carp samples compared with microbial enumeration. Before storage, Macrococcus and Aeromonas were the prevalent populations in the control samples, but cinnamon essential oil decreased the relative abundance of Macrococcus in the treated samples. Variability in the predominant microbiota in different samples during chilled storage was observed. Aeromonas followed by Lactococcus were the major contaminants in the spoiled control samples. Microbial enumeration also observed relatively higher counts of Aeromonas than other spoilage microorganisms. Compared with the control samples, cinnamon essential oil inhibited the growth of Aeromonas and Lactococcus were the predominant components in the treated samples on day 10; plate counts also revealed a relatively high level of lactic acid bacteria during refrigerated storage. However, there were no significant differences ( P > 0.05) in the composition of dominant microbiota between these two treatments at the end of the shelf-life. Furthermore, cinnamon essential oil treatment was more effective in inhibiting the increase of TVB-N and the accumulation of biogenic amines (especially for putrescine and cadaverine levels). Based primarily on sensory analysis, the use of cinnamon essential oil extended the shelf-life of vacuum-packaged common carp fillets by about 2 days. [ABSTRACT FROM AUTHOR]

The impact of different concentrations of Na + , K + , Ca 2+ , Mg 2+ , Fe 2+ , and Zn 2+ on the degradation of adenosine triphosphate (ATP) and the influence of these ions on the activity of adenosine monophosphate deaminase (AMP-deaminase) and acid phosphatase (ACP) in common carp fillets ( in vivo ) during 4 °C storage was examined. The content of ATP, inosine monophosphate (IMP), and hypoxanthine (Hx), and the activity of AMP-deaminase and ACP were determined. Results indicated that the effects of different concentrations of six kinds of metal ions on AMP-deaminase and ACP were not the same. Na + , K + , Fe 2+ , and Zn 2+ enhanced AMP-deaminase activity, which led to the rapid degradation of ATP and to the generation of a large quantity of IMP within a short time. Ca 2+ and Mg 2+ delayed the change in AMP-deaminase and ACP activity in carp and caused a further delay in the degradation of ATP. Fe 2+ and Zn 2+ inhibited ACP activity, which reduced the decomposition of IMP and the formation of Hx. [ABSTRACT FROM AUTHOR]