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Salted egg yolks have a tender, loose, gritty, and oily texture and are commonly employed as fillings in baked goods. This study investigated the formation mechanism of egg yolk gels using three different pickling methods: NaCl, sucrose, and mixed groups. The results revealed that of these pickling methods, egg yolks pickled with the mixture had the lowest moisture content (11.59% at 25°C and 10.21% at 45°C), almost no free water content, and the highest hardness (19.11 N at 25°C and 31.01 N at 45°C). Intermolecular force measurements indicated that pickling with the mixture mitigated the surface hardening effect of sucrose and facilitated protein cross-linking. Moreover, confocal laser scanning microscopy of the egg yolk gels pickled with the mixture displayed macromolecular aggregates and oil exudation, suggesting that this method partially disrupted the lipoprotein structure and notably promoted yolk protein aggregation and lipid release. Overall, egg yolks formed a dense gel via the mixed pickling method owing to the ionic concentration and dehydration effects. These findings show the impact of NaCl and sucrose in pickling egg yolks, providing a crucial foundation for developing innovative and desirable egg yolk products. PRACTICAL APPLICATION: This study introduces a novel pickling strategy that combines sucrose and NaCl for egg yolk processing. The egg yolk pickled using this method exhibited improved quality according to the evaluated textural characteristics, moisture distribution, and protein aggregation behavior. The findings may broaden the use of sucrose as a pickling agent for egg yolk processing and provide new ideas for developing and producing pickled eggs and other food products.
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Proteínas del Huevo , Yema de Huevo , Manipulación de Alimentos , Cloruro de Sodio , Sacarosa , Agua , Yema de Huevo/química , Sacarosa/química , Cloruro de Sodio/química , Agua/química , Proteínas del Huevo/química , Manipulación de Alimentos/métodos , Agregado de Proteínas , Geles/química , Animales , PollosRESUMEN
Degradation efficiency and catalyst stability are crucial issues in the control of organic compounds in wastewater by advanced oxidation processes (AOPs). However, it is difficult for catalysts used in AOPs to have both high catalytic activity and high stability. Combined with the excellent activity of cobalt/copper oxides and the good stability of carbon, highly dispersed cobalt-oxide and copper-oxide nanoparticles embedded in carbon-matrix composites (Co-Cu@C) were prepared for the catalytic activation of peroxymonosulfate (PMS). The catalysts exhibited a stable structure and excellent performance for complete phenol degradation (20 mg L-1) within 5 min in the Cu-Co@C-5/PMS system, as well as low metal-ion-leaching rates and great reusability. Moreover, a quenching test and an EPR analysis revealed that ·OH, O2·-, and 1O2 were generated in the Co-Cu@C/PMS system for phenol degradation. The possible mechanism for the radical and non-radical pathways in the activation of the PMS by the Co-Cu@C was proposed. The present study provides a new strategy with which to construct heterostructures for environmentally friendly and efficient PMS-activation catalysts.
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Edible films based on egg white protein (EWP) were prepared, and it were modified by high-intensity ultrasound (HIUS) to improve the functional properties. The findings indicated the properties of EWP films were improved at the appropriate time of HIUS treatment. With the increase of ultrasonic time, water vapor permeability (WVP) and tensile strength (TS) of EWP films ascended and then declined, and the best performance (3.30 g·mm/ m2·h·KPa for WVP, and 7.28 MPa for TS) was achieved when ultrasonic time was 10 min. Thermogravimetric analysis exhibited ultrasound could enhance the thermal stability of EWP films. The SEM reflected moderate ultrasonic treatment could make the EWP films smoother. The FTIR spectroscopy and X-ray diffraction patterns of EWP films were changed by HIUS, which illustrated the secondary structure of the protein was altered. The transverse relaxation curve obtained by LF-NMR analysis showed the tightness between water and the films.
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Proteínas del Huevo , Vapor , Proteínas del Huevo/química , Permeabilidad , Resistencia a la Tracción , Difracción de Rayos XRESUMEN
Carboxymethyl cellulose (CMC) films containing lysozyme (Lys) were prepared in this study and changes in properties of the films were investigated. Enhancement in mechanical properties was observed with increased Lys, maximum (0.05 g/100 mL) reached to 39.07 MPa (TS) and 25.04 % (EAB). Meanwhile, water resistance ability improved, the minimum (0.05 g/100 mL) reached to 0.42 g·mm·(m2·h·KPa)-1, 84.62 % of pure CMC film. Thermogravimetric test showed better thermal stability of films. Scanning electron microscope illustrated that few cracks on surface of films. Fourier Transform infrared spectroscopy supported that more intermolecular hydrogen between Lys and CMC was formed with increased Lys, yet keeping increasing formed less intermolecular hydrogen. X-ray Diffraction observed the aggregated Lys by crystal structure. Antibacterial test showed an inhibitory effect on two common food-borne pathogens. Weight loss experiment indicated that films reduced the dry consumption of meat. Overall, the modification of CMC film by adding Lys was effective.
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Antibacterianos , Carboximetilcelulosa de Sodio , Antibacterianos/química , Antibacterianos/farmacología , Carboximetilcelulosa de Sodio/química , Embalaje de Alimentos/métodos , Hidrógeno , Muramidasa , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Capacitive deionization (CDI) has gained increasing attention as an environmentally friendly and energy-efficient technology for brackish water desalination. However, traditional CDI electrodes still suffer from low salt adsorption capacity and unsatisfactory reusability, which inhibit its application for long-term operations. Herein, we present a facile and effective approach to prepare Co and Co3O4 nanoparticles co-incorporating nitrogen-doped (N-doped) carbon nanotubes (Co-Co3O4/N-CNTs) via a pyrolysis route. The Co-Co3O4 nanoparticles were homogeneously in-situ encapsulated in the inner channels of the conductive CNTs to form a novel and efficient CDI electrode for the first time. The encapsulation of Co-Co3O4 nanoparticles in CNTs not only inhibits the Co leaching but also significantly enhances the desalination capacity. The morphology, structure, and capacitive desalination properties of the Co-Co3O4/N-CNTs were thoroughly characterized to illuminate the nano-confinement effects and the key roles of the interaction between cobalt species in the CDI performance. The co-existing metallic cobalt and cobalt oxides act as the roles of effective active sites in the CDI performance. As a consequence, the optimum Co-Co3O4/N-CNTs electrode displays an outstanding desalination capacity of 66.91 mg NaCl g-1 at 1.4 V. This work provides insights for understanding the nano-confinement effects and the key roles of the interaction between cobalt species on the CDI performance.
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Nanotubos de Carbono , Cobalto , Electrodos , Nanotubos de Carbono/química , Nitrógeno , Óxidos , Cloruro de SodioRESUMEN
Inorganic photocatalysts became an essential and powerful tool for the remediation of polluted water. However, important limitations of photocatalysts in their colloidal form, especially nanosized, remain. For instance, their separation from water after use and recovery, which can be particularly demanding, time- and energy-wise. Considering such aspects, supported catalysts bear significant advantages. However, efforts still have to be made to develop processes that allow the permanent and efficient immobilization of inorganic photocatalysts in sustainable conditions, in order to maintain the advantages of supported catalysts over colloidal ones. Herein, we report the use of an aqueous-phase plasma-aided grafting (APPAG) process to produce functional and efficient hybrid photocatalysts. More specifically, based on cold plasma discharge (CPD), ZnO/Bi2MoO6 heterojunctions were permanently immobilized on polymer supports generated by 3D-printing, with fractal-inspired designs. Three different approaches of the APPAG process have been successfully used for the immobilization of the inorganic phase, that is core-shell-assisted direct grafting, indirect grafting and in situ complexation-assisted precipitation (ISCAP). Noticeably, the latter technique has never been reported before to our knowledge. These three immobilization routes rely on different strategies and yield to distinct morphological specificities, but all allow using mild synthesis conditions and producing stable, active, permanently immobilized coatings of photocatalysts. Regarding the preparation of the organic supports, two sorts of additive manufacturing (AM) technologies were employed, namely fused-deposition modeling (FDM) and liquid crystal diode (LCD)-based SLA (stereolithography). The use of fractal geometries combined with AM permits the production of supports with relatively high surface areas, in a single processing step. Overall, the three plasma-based immobilization methods revealed to be efficient and the performance of the different hybrid photocatalysts have later been assessed through the photodegradation of Rhodamine B dye under simulated sunlight irradiation and visible light only, with promising results.
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Dual heteroatom-codoped carbon materials have attracted great interest in electrochemical researches due to a synergistic effect. However, evaluation and analyses of promotional effect of codoped carbons materials as electrodes on capacitive deionization have not been extensively studied. Here we prepare N, S- codoped porous carbon nanosheets (N, S-CN-x, x indicates carbonization temperature) by one-pot molten salt strategy as efficient electrodes for electrosorptive desalination. The N, S-CN sample carbonized at 600⯰C (N, S-CN-600) possesses a high specific area, unique meso-/microporous interconnected structure, fine wettability, and double functional groups on the surface. Meanwhile Raman spectra revealed N, S-CN materials have a higher degree of structure defects than undoped and solely N or N-doped carbon samples. Additionally, systematic investigation demonstrates that N, S-codoping has distinct promotional effect on electrochemical properties (higher specific capacitance and lower internal impedance) and capacitive deionization performance compared with undoping, solely N or S doping. What's more, N, S-CN-600 displays great cycling stability and an outstanding deionization capacity of 55.79â¯mgâ¯g-1 at 1.4â¯V in a 330â¯mgâ¯L-1 NaCl solution. Hence, the N, S-codoped carbon nanosheets should be promising electrode materials for capacitive deionization. Our work could pave a way for the application of multiple heteroatom codoped carbon materials in capacitive deionization.
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This study aim to explore an effective approach of persulfate (PS) activation based on multi-walled carbon nanotubes (CNTs) for the phenol degradation. The nitric acid/annealing modified CNTs were obtained by oxidation with concentrated nitric acid followed by annealing at various high temperatures (400-1000⯰C). The modified CNTs catalysts were characterized and their catalytic degradation performances of phenol with PS were investigated. The results reveal that the modified CNTs can obviously enhance the phenol removal. The catalytic activity is improved by nitric acid modification and obviously influenced by the annealing temperature. PS concentration and solution pH could also affect the catalytic degradation of phenol. The mechanism of enhanced PS activation by the nitric acid/annealing modified CNTs was proposed that the nitric acid modification resulted in more defective edges and oxygen-containing groups, and subsequent annealing at high temperate facilitated the conversion of sp3 to sp2 carbon, then the catalytic activity for PS activation was enhanced by the active sites of CO group and sp2-hybridized carbon at the defective edges. In addition, a non-radical process of phenol degradation was demonstrated in terms of the radical quenching tests and electron paramagnetic resonance (EPR) spectra analyses. It is suggested that 1O2 is likely the main reactive specie generated in PS activation by the modified CNTs for the phenol removal.
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Nanotubos de Carbono/química , Ácido Nítrico/química , Fenol/química , Sulfatos/química , Catálisis , Oxidación-ReducciónRESUMEN
An Fe-Cu binary oxide was fabricated through a simple co-precipitation process, and was used to remove Sb(III) from aqueous solution. X-ray diffraction, scanning electron microscopy, energy dispersive X-ray and N2 adsorption-desorption measurements demonstrated that the Fe-Cu binary oxide consisted of poorly ordered ferrihydrite and CuO, and its specific surface area was higher than both iron oxide and copper oxide. A comparative test indicated that Fe/Cu molar ratio of prepared binary oxide greatly influenced Sb(III) removal and the optimum Fe/Cu molar ratio was about 3/1. Moreover, a maximum adsorption capacity of 209.23 mg Sb(III)/g Fe-Cu binary oxide at pH 5.0 was obtained. The removal of Sb(III) by Fe-Cu binary oxide followed the Freundlich adsorption isotherm and the pseudo-second-order kinetics in the batch study. The removal of Sb(III) was not sensitive to solution pH. In addition, the release of Fe and Cu ions to water was very low when the pH was greater than 6.0. X-ray photoelectron spectroscopy analysis confirmed that the Sb(III) adsorbed on the surface was not oxidized to Sb(V).
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Antimonio/química , Cobre/química , Compuestos Férricos/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Adsorción , Cinética , Oxidación-ReducciónRESUMEN
The present article summarizes antimony mine distribution, antimony mine drainage generation and environmental impacts, and critically analyses the remediation approach with special emphasis on iron oxidizing bacteria and sulfate reducing bacteria. Most recent research focuses on readily available low-cost adsorbents, such as minerals, wastes, and biosorbents. It is found that iron oxides prepared by chemical methods present superior adsorption ability for Sb(III) and Sb(V). However, this process is more costly and iron oxide activity can be inhibited by plenty of sulfate in antimony mine drainage. In the presence of sulfate reducing bacteria, sulfate can be reduced to sulfide and form Sb(2)S(3) precipitates. However, dissolved oxygen and lack of nutrient source in antimony mine drainage inhibit sulfate reducing bacteria activity. Biogenetic iron oxide minerals from iron corrosion by iron-oxidizing bacteria may prove promising for antimony adsorption, while the micro-environment generated from iron corrosion by iron oxidizing bacteria may provide better growth conditions for symbiotic sulfate reducing bacteria. Finally, based on biogenetic iron oxide adsorption and sulfate reducing bacteria followed by precipitation, the paper suggests an alternative treatment for antimony mine drainage that deserves exploration.