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The complex composition of braised pork, including lean meat, pigskin, and fat, makes it difficult for sensory evaluation of its texture properties. This study investigated the correlation between sensory texture attributes and physicochemical properties to achieve an objective and comprehensive evaluation of the texture of braised pork. Sensory analysis demonstrated that the overall texture acceptability of braised pork was significantly and negatively influenced by sensory texture attributes (including sensory hardness, chewiness, and toughness), while it was positively impacted by sensory adhesiveness, softness, and juiciness. Shear force and texture profile analysis (TPA) variables, reflecting mastication behavior, were used to characterize the textural properties of braised pork. They were closely related to water distribution, with a higher proportion of immobilized water (P21), indicating a higher water holding capacity and a more tender texture. Correlation analysis between sensory texture attributes and physicochemical properties through partial least squares regression further revealed significant associations between shear force, TPA variables, and sensory texture attributes. Moreover, the proportion of immobilized water (P21) significantly and negatively affected sensory hardness and chewiness, whereas the proportion of free water (P22) significantly influenced sensory toughness. Sensory texture attributes could be well predicted by the physicochemical properties by projecting test samples onto calibration models established by known samples. Therefore, a combination of sensory and instrumental measures can reliably reflect the texture properties of braised pork. Practical Application: The combination of sensory and instrumental methods is an effective strategy to accurately and objectively evaluate the texture properties of braised pork, which overcomes the limitations caused by the complexity of the composition and texture traits of braised pork. The accurate evaluation and standardization of texture properties is an important premise for the repeatable and stable cooking of traditional braised pork. Furthermore, this research method and findings can also be applied to guide the procedural optimization of smart appliances (e.g., induction cookers) for cooking braised pork. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW) heterostructures identify the advantage of integrating excellent properties of the stacked two-dimensional (2-D) materials by vdW interactions, thereby have gained increasing attention in optoelectronic applications recently. However, heterostructures with type-II band aligning and direct bandgap are still scarce for optoelectronics. Herein, within the framework of density functional theory (DFT) calculations, we predict the indium selenide/antimonene heterostructure as a promising candidate for optoelectronic applications. The most energetically stable configuration of indium selenide/antimonene heterostructure presents a direct bandgap of 0.97 eV at HSE06 level. Remarkably, indium selenide/antimonene heterostructure exhibits a type-II band alignment, indicating its favorable capability of electron–hole separation. Carrier mobility computations show that indium selenide/antimonene heterostructure possesses both high electron mobility and hole mobility of up to 103 cm2 V−1 s−1, which are superior to that of any individual monolayer InSe and antimonene. The light absorption and photocurrent calculations reveal that InSe/antimonene heterostructure is sensitive to visible and ultraviolet light. The power conversion efficiency of an indium selenide/antimonene thin-film solar cell is up to 17.2%. The multifunctionality endows the indium selenide/antimonene heterostructure a potential candidate for photovoltaic devices and photodetectors. [ABSTRACT FROM AUTHOR]

Pea protein was used to prepare the Maillard reaction products (MRPs) through enzymatic hydrolysis and further thermal reaction with reducing sugar. A pronounced saltiness improvement in NaCl solution was observed by the addition of hydrolysates and their MRPs. Low-molecular-weight pea peptides had the strongest effect of saltiness and umami enhancement. The saltiness-enhancing effect of MRPs derived from hexoses was higher than that from pentoses. Molecular weight distribution and amino acid content of MRPs prepared under different time revealed that the hydrolysis of peptides and the initial Maillard reaction of hydrolysis products were dominant at 1 h of thermal reaction. With the extension of heating time, further reaction of small tasty peptides led to a decrease in the saltiness enhancement. The kokumi attribute was mainly contributed by the MRPs of small peptides. When the dosage of MRPs was 0.7% coupled with 0.4% NaCl, the saltiness of the solution was higher than that of the control (0.5% NaCl), which meant that the saltiness was not weakened even when the NaCl concentration was reduced by 20%. The results of the electronic tongue analysis were consistent with that of the sensory evaluation. [ABSTRACT FROM AUTHOR]

Photocatalytic water splitting, as an artificial photosynthesis process for producing clean hydrogen energy, has recently attracted extensive attention due to its bright prospects for solving the shortage of fossil energy and environmental crisis. However, it is still challenging to achieve highly efficient overall water splitting because of the unsuitable electronic structure and the strong dependence on the noble metal co-catalysts to date. The development of photocatalytic water splitting is therefore immensely urgent to enlarge the uptake of photocatalysts by exploring novel compounds. Herein, we propose a novel two-dimensional (2D) pentagonal SiAs2 (penta-SiAs2) photocatalyst suitable for water splitting based on first-principles calculations. Using a hybrid functional, we demonstrate the bandgap of 2D penta-SiAs2 to be 2.35 eV, and its band-edges perfectly stride the redox potential of water. Most importantly, this material possesses both highly desirable carrier mobilities and strong light absorption in the visible and ultraviolet (UV) regions, which are superior to those of most previously reported 2D materials. Furthermore, the free energies suggest that hydrogen and oxygen evolution reactions are feasible with penta-SiAs2. These extraordinary characteristics make penta-SiAs2 a promising 2D material for photocatalytic water splitting and provide a possible route for the future experiment scheme. [ABSTRACT FROM AUTHOR]

Mechanical properties are the important parameters of the film which reflected the resistance of the films during their shelf life. In order to evaluate the stability of zein films preserved at different temperature and relative humidity (RH), tensile strength (TS) and elongation at break (EB) of zein films plasticized with glycerol and PEG‐400 were observed during storage. Results showed that the EB decreased and TS increased during the first 6 days of storage at different RH and temperatures. RH which brought a maximum change in TS and EB were 43% and 65%, respectively. Films preserved at RH of 80% for 18 days lost its extensibility. Statistical analysis results showed that the correlations between the free sulphydryl content and mechanical properties at RH 43%, and between the moisture content and mechanical properties at RH 80% were more significant. A model was proposed to explain the change in TS and EB during zein film storage. Practical applications: Zein is commonly produced from the by‐product of bio‐ethanol and starch industries and has excellent film‐forming properties. Pure zein film is brittle, which has limited their application. Many researches have focused on the improvement of the mechanical properties of zein films. As a packing material, zein film should have excellent stability during the shelf life of the packaged food. So a systematic study about the effect of temperature and relative humidity on the mechanical properties of zein film plasticized with glycerol and PEG‐400 during storage is necessary. The results presented in this paper would highlight the suitable applying environment of zein films, either actual or potential. [ABSTRACT FROM AUTHOR]

Maillard reaction intermediate (MGX) generated from glutathione and xylose in aqueous medium was prepared via the Maillard reaction performed under a two‐stage temperature increase process. The purified MGX was identified by Fourier‐transform infrared spectroscopy, mass spectrometry, and nuclear magnetic resonance as N‐(1‐deoxy‐d‐xylulos‐1‐yl)‐glutathione (Amadori compound, C15H25O10N3S) with five main isomers. The method of Maillard reaction performed under a two‐stage temperature increase process was further verified by high‐performance liquid chromatography. The optimal reaction time and temperature for the preparation of MGX was determined as 60 min at 90 °C. The yield of MGX was increased from 8.60% to 55.52% through thermal reaction coupled with vacuum dehydration. In addition, rapid and more Maillard‐type volatile compounds were formed in MGX during thermal treatment than that in Maillard reaction products or glutathione‐xylose mixture. Beside, MGX possessed more pleasing meat‐like volatile profile compared with the Amadori compound of glutamic acid‐xylose (AAX), cysteine‐xylose (ACX), and glycine‐xylose (AGX). Therefore, it suggested that the MGX had the potential to achieve a better flavor formation during thermal treatment. Practical Application: Maillard reaction intermediates, such as Amadori or Heyns rearrangement products (ARP or HRP), are important flavor precursors, which possess stable physicochemical properties, but tend to degrade into flavor compounds at high temperatures. Maillard reaction intermediate from glutathione and xylose acts as primary flavor enhancers to complete Maillard reaction to produce flavors in the subsequent thermal processing, which can significantly improve and stabilize the flavor quality of the meaty food, and deserves a very broad application prospects. The new developed method will be a significant theoretical basis on research preparation and properties of Maillard reaction intermediates in complex food systems. [ABSTRACT FROM AUTHOR]

The sensing performances of SF6 decompositions, including HF, SOF2, SO2, SO2F2, and H2S, adsorption on monolayer tellurene have been investigated by means of density functional theory (DFT) calculations in this letter. The attained results show that the monolayer tellurene is preferable for SF6 decomposition components, especially for SO2 and SOF2, exhibiting favorable adsorption strength and apparent charge transfers. Besides, the calculated density of states (DOS) further reveals the electronic properties are obviously changed after SO2 and SOF2 adsorption. These results signify that tellurene-based gas sensor is a potential candidate for detecting SF6 decompositions in high-voltage insulation equipment. [ABSTRACT FROM AUTHOR]

Amadori rearrangement product (ARP) derived from glutamic acid (Glu) and xylose (Xyl) was prepared by aqueous Maillard reaction. Subsequently, ion exchange chromatography, MS, and NMR were used for purification and identification, confirming that the molecular formula of ARP was C10H17NO8, namely N‐(1‐deoxy‐α‐D‐xylulos‐1‐yl)‐glutamic acid, with a molecular mass of 279 Da. To improve the aqueous yield of ARP, a thermal reaction coupled with vacuum dehydration was used and the yield of ARP was increased from 2.07% to 75.11%. Furthermore, flavor formation capacity of ARP by a thermal treatment simulated to a baking process was compared with Maillard reaction products, Maillard‐dehydration reaction products, and Glu‐Xyl mixture. The results indicated that a larger amount of volatile flavor compounds and a biscuit‐like, burnt aroma was generated rapidly from the mixture of ARP and unreacted Glu‐Xyl, which could be a potential flavor enhancer for baked foods. Practical Application: Maillard reaction performed in aqueous medium through thermal reaction combined with vacuum dehydration is a novel and practical technology that could be widely used to produce Maillard reaction intermediates (MRIs), such as Amadori or Heyns rearrangement products, which are regarded as significant nonvolatile aroma precursors and have stable physical and chemical properties compared with Maillard reaction products (MRPs). MRI derived from glutamic acid and xylose is a potential substitute of MRPs for flavorings preparation and shows a great capacity to generate fresh flavors in a short time at high temperature, which meets the requirements of baking foods. Therefore, the new developed method could be a promising tool for MRI preparation and application in food and flavoring industries. [ABSTRACT FROM AUTHOR]

In order to give the boiled sunflower seeds the rich taste, caramel aroma, and improved oxidation resistance, Maillard peptides were added to sunflower seeds in this research. Sunflower seeds sample 5 (SFS5) and sunflower seeds sample 2 (SFS2) were prepared by adding Maillard peptides of sunflower seeds (K), gluten (G), and corn (Y), at different ratio (SFS2, K:G = 8:2; SFS5, K:G:Y = 8:1:1). Component analysis showed that SFS5 and SFS2 were significantly higher in umami amino acids than the control (SFS0) without Maillard peptides. SFS5 and SFS2 contained more hybrid compounds such as pyrazines and furans which contributed to the caramel aroma of sunflower seeds. Electronic tongue analysis revealed the higher response values of umami, salty, and continuity taste for SFS5 and SFS2 than those of SFS0. Sensory evaluation results showed that the sunflower flavor, caramel aroma, umami characteristic, and overall acceptability of SFS5 and SFS2 were higher than that of SFS0. The chemical results showed that under accelerated oxidation, the SFS5 and SFS2 had significantly lower peroxide value and acid value than SFS0. [ABSTRACT FROM AUTHOR]

The Maillard reaction end‐products (MRPs) and intermediate (MRI, N‐(1‐deoxy‐α‐D‐xylulos‐1‐yl)‐phenylalanine) derived from xylose (Xyl) and phenylalanine (Phe) model system were synthesized in an aqueous medium, and their antioxidant activity was evaluated. Both the MRPs and N‐(1‐deoxy‐α‐d‐xylulos‐1‐yl)‐phenylalanine exhibited the Fe2+ chelating activity at their addition concentration of 2 to 12 mg/mL. While their reducing power, free radical scavenging activity, and inhibition effect on lipid peroxidation were observed at a lower addition concentration of only 0.2 to 1.2 mg/mL. The free radical scavenging activity was improved with the increase in their concentration, and a time‐dependent scavenging effect of the MRI was also shown in the results. However, a weak chelating activity of Xyl‐Phe on Fe2+ in a concentration‐dependent manner was observed, but no significant free radical scavenging activity or reducing power of Xyl‐Phe was found. Based on these results, possible free radical scavenging pathway of the MRI was proposed. As the MRI showed lower antioxidant activity than MRPs, the application of the MRI in combination with MRPs as an antioxidant was proposed in cooked or semi‐processed foods to avoid the deterioration induced by oxidation. Practical Application: The Maillard reaction intermediates (MRIs) showed antioxidant activity and could be applied in foods as both antioxidants and flavor enhancer. The MRIs will probably extend the shelf‐life of lipid rich foods and could be the substitute of artificial antioxidants. [ABSTRACT FROM AUTHOR]

Blue phosphorene (Blue-p), an allotrope of black phosphorene, has attracted extensive interest due to its hexagonal crystal with a flat arranged layer of phosphorus atoms. However, the indirect band gap of Blue-p greatly hinders its applications in optoelectronics. By stacking both boron phosphide (BP) and the organic molecule 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) with Blue-p, we construct BP/Blue-p and F4TCNQ/Blue-p heterostructures. We reveal that the BP/Blue-p heterostructure possesses a direct band gap of 0.605 eV and is tunable via in-plane strain and an external electric field. Moreover, it also has remarkable optical absorption in the UV region and enhanced transport properties. Furthermore, by doping with F4TCNQ, the F4TCNQ/Blue-p heterojunction displays type-II semiconducting properties with a flat valence band and Van Hove singularities at the Fermi level, which can be used to achieve extremely low in-band tunneling, yielding low static power dissipation and large drive currents in the ON regime of transistors. Due to the superior electronic, optical and transport properties, Blue-p-based heterostructures are promising candidates for electronic and optical device applications. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have extraordinary properties and multifunctional applications; thus, prodigious efforts have been made in the exploration of novel 2D materials. In this study, 2D hexagonal YN (h-YN) is predicted based on theoretical calculations. By assessing its phonon spectrum, ab initio molecular dynamics and elastic constants, the h-YN monolayer is proven to exhibit satisfying thermal, dynamic and mechanical stability. Unique from most of the reported 2D transition metal mononitrides, which exhibit metallic characteristics, monolayer h-YN is a semiconductor with an indirect bandgap of 2.322 eV. In particular, the electronic structures of h-YN present unusually insensitive responses to tensile or compressive strain due to valence orbital hybridization. Carrier mobility calculations suggest that monolayer h-YN possesses a high electron mobility of up to 104 cm2 V−1 s−1 and hole mobility of up to 103 cm2 V−1 s−1 in the zigzag and armchair orientations. Moreover, few-layer h-YN displays evident semiconductor performances and dispersive conductive bands, indicating light electron effective masses and excellent electron transport capabilities. This pronounced carrier mobility, insensitive electronic responses to strain and light electron effective masses of its few-layer structures demonstrate that h-YN is a promising candidate in future nanoscale electronic devices in high-strain conditions. [ABSTRACT FROM AUTHOR]

The adsorption of gas molecules, such as N2, O2, CO2, H2O, CO, NO, NO2, H2S, NH3, and SO2 on monolayer C3N has been investigated by means of first-principles and non-equilibrium Green’s function calculations. We show that monolayer C3N is preferable for the NO2 and SO2 molecules with suitable adsorption strength and apparent charge transfers. Moreover, the I – V characteristics of C3N show clear variations after the adsorption of NO2 and SO2. Such sensitivity and selectivity to NO2 and SO2 molecules make C3N a promising candidate for highly sensitive gas sensor. [ABSTRACT FROM PUBLISHER]

Maillard reaction products (MRPs) were prepared from mushroom hydrolysate (MH) by heating with d-xylose and l-cysteine at various temperatures (100 °C–140 °C) for 2 h at a pH of 7.4. The sensory characteristics of MH and MRPs were evaluated by panelists and volatile compounds were analyzed by GC/MS. Additionally, partial least squares regression (PLSR) was performed to analyze the correlation between quantitative sensory characteristics and GC/MS data. GC/MS results revealed that higher reaction temperature resulted in more nitrogen and sulfur containing compounds in MRPs while alcohols, ketones and aldehydes were the major flavor compounds obtained in MH. PLSR results showed that 3-phenylfuran and 2-octylfuran were the compounds responsible for the caramel-like flavor; 1-octen-3-ol, (E)-2-octen-1-ol and geranyl acetone were significantly and positively correlated to mushroom-like flavor, whereas, 2-thiophene-carboxaldehyde, 2,5-thiophenedicarboxaldehyde and 3-methylbutanal positively affected MRPs meat-like attribute. Overall, 125 °C was identified as the optimal temperature for preparing MRPs with abundant volatile compounds and favorable sensory characteristics; the concentration of free amino acids and 5′-GMP, which are associated with the umami taste, in MRPs derived under 125 °C were 3 to 4 times higher than those in MH. [ABSTRACT FROM AUTHOR]

Random characteristics of the dynamic heterogeneous structure in gas-solid fluidization have been studied by reconstructing voidage time series. It is indicated that the dense phase, the dilute phase and the dense/dilute cycle elements show random dynamic behavior satisfying the so-called Weibull distribution, three parameters of which change regularly with operating conditions. [ABSTRACT FROM AUTHOR]