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关键词： Protein isolates   Sonication   Physicochemical properties   Chenopodium quinoa   Phaseolus vulgaris and Lens culinaris  

摘要： Sonicated protein isolates were recovered from Chenopodium quinua, Phaseoulus vulgaris and Lens culinaris to develop a functional matrix by assessing the physicochemical and functional properties. The plant protein isolates were prepared from powdered materials followed by sonication in alkaline medium using a Box-Behnken design. pH (6-10), a buffer-to-material ratio (5:1 to 15:1) and sonication time (0-20 min) were taken as independent variables, whereas protein yield was taken as the dependent variable. A pH of 9, 20 min treatment, and a buffer-to-material ratio of 5:1 were the optimal extraction conditions for quinoa and black beans, whereas a 1:10 ratio was suitable for lentils. Sonication in alkaline medium caused partial protein unfolding and these isolates;in turn, the molecular weight affected the emulsifying activity and stability. Moreover, sonication had a strong effect on the gelation temperature, emulsifying activity, the water, and oil sorption. Sonication improved protein yield and exposed amino acids such as glutamic acid, aspartic acid, leucine and glycine. In turn, thiol groups were responsible for the increased in gelation temperature. The better gelling property coupled with high emulsifying property of these proteins show potential application as protein emulsifiers in the production of gels, sausages, and pet foods.

关键词： Functional properties   Optimization   Physicochemical properties   Protein isolate   Response surface methodology   Vicia villosa  

摘要： Vicia villosa )V. villosa ( seed is considered a good source of protein, fiber, and minerals (iron, magnesium, potassium, etc.) and is helpful for human health. This study focused on optimizing the extraction of V. villosa seed protein and investigating the physicochemical and functional properties of V. villosa protein isolate (VVPI) as a food additive. The response surface methodology (RSM) was applied to optimize the extraction process of protein isolate using the face central composite design (FCCD). The optimal conditions for maximum protein yield (12.47%), protein content (87.90 %), and protein solubility (8.17 mg/mL( were obtained under conditions of pH 11 and extraction time of 26 min. The primary VVPI amino acids glutamine (Glu) and asparagine (Asp) were 16.4% and 10.16%, respectively. The results indicated that VVPI had significant solubility, foaming, and emulsifying properties, which the lowest of these properties were observed at the isoelectric point (pI). Also, VVPI showed that it has water holding capacity (WHC) and oil absorption capacity adequate. The denaturation temperature (76.17 degrees C) of VVPI was determined by using a differential scanning calorimeter (DSC). Scanning electron microscopy (SEM) showed that VVPI has a rough surface. Regarding the good nutritional and functional properties of VVPI, it can be recommended to be used in various food formulations as an additive.

关键词： Chlorine compounds  

摘要： The development of a sustainable ion-conducting solid electrolyte is an intense area of research because of its potential application in all-solid-state batteries. In the present work, ion-conducting electrolyte membranes based on water-soluble biopolymer sodium alginate and sodium perchlorate (NaClO4) are prepared and analyzed. The complexation between NaClO4 and the sodium alginate biopolymer is well established by Fourier transform infrared spectroscopy (FTIR) analysis. The inclusion and the impact of NaClO4 concentration producing changes in the crystalline/amorphous nature of the membrane is recognized by the X-ray diffraction (XRD) technique. The thermal analysis by differential scanning calorimetry (DSC) reveals the changes in glass transition temperature (T-g) for various sodium alginate/NaClO4 compositions. The membrane with 60 wt% NaClO4:40 wt% sodium alginate exhibits maximum ion conductivity of 2.291 x 10(-3) S cm(-1) at room temperature possessing a transference number of 0.96 and a potential window of 3.4 V. An all-solid-state primary battery has been constructed which is found to manifest an open-circuit potential of 3.14 V. The present investigation is very appropriate and promising for utilizing the prepared biopolymer membranes for the application of the sodium-ion battery.

关键词： acorn kernels   crystallinity   endogenous polyphenols   in vitro digestibility   starch  

摘要： The effects of endogenous polyphenols in acorn kernels on granule morphology, crystal properties, and in vitro digestibility of starch are investigated. The granule surface smoothness, relative crystallinity, short-range molecular order, and starch hydrolysis rate increase after the removal of polyphenols from acorn flour. With the addition of polyphenol extracts, the hydrolysis rates of acorn, corn, potato, and chestnut starches are all reduced, and the free-polyphenol extract shows higher inhibitory activity than the bound-polyphenol extract. These results are expected to be helpful for understanding the low digestibility of starch in acorn kernels, which is attributed to the inhibitory effects of polyphenols on the activities of alpha-amylase and alpha-glucosidase, but not the increase of long and short-range molecular orders of starch.

关键词： corn starch   extrusion-assisted isolation   physicochemical properties   wet-milling  

摘要： The yield, physicochemical properties, and digestibility of corn starch isolated by conventional wet-milling (CS), extrusion-assisted H2SO3 wet-milling (EHS), and extrusion-assisted l-cysteine wet-milling (ELS) are investigated. The yield of EHS is significantly higher than that of CS and ELS (p < 0.05). There are no significant differences (p > 0.05) in purity among isolated starches. The results of scanning electron microscopy, polarized light microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and differential scanning calorimeter reveal that extrusion induced unobvious changes in morphology, surface, crystalline pattern, ordered structures, and thermal properties of isolated starch (p > 0.05). However, the swelling power, solubility, L* value, and peak viscosity of EHS are higher than those of ELS and CS. Extrusion-assisted treatment effectively improves the freeze-thaw stability and digestibility of isolated starch. The results of this study suggest that the extrusion-assisted wet-milling method can be used as an ideal alternative to conventional wet-milling in the isolation of corn starch.

关键词： Solid oxide electrolyzer cells (SOEC)   Metallic interconnects   Cobalt manganese spinels   Oxidation kinetics   Electrical conductivity  

摘要： The Crofer 22 H ferritic steel substrate was coated with an Mn1.45Co1.45Cu0.1O4 spinel by means of electrophoresis. After high-temperature oxidation under thermal cycling conditions, the physicochemical properties of the obtained system were evaluated. During 48-h cycles that involved heating the samples up to temperatures of either 750 or 800 degrees C, the oxidation kinetics of both coated and unmodified steel approximately obeyed the parabolic rate law. The unmodified steel was oxidized at a higher rate than the system consisting of the substrate and the coating. In its bulk form, the spinel consisted entirely of the cubic phase and it exhibited high electrical conductivity. The Mn1.45Co1.45Cu0.1O4 coating, on the other hand, was compact and consisted of two phases-the cubic and the tetragonal one-and it was characterized by good adhesion to the metallic substrate. After cyclic oxidation studies conducted for the two investigated temperatures (750 or 800 degrees C), the coating was determined to provide a considerable improvement in the electrical properties of the Crofer 22 H ferritic steel, as demonstrated by the area-specific resistance values measured for the steel/coating system. The evaporation rate of chromium measured for these samples likewise indicates that the coating is capable of acting as an effective barrier against the formation of volatile compounds of chromium. The Mn1.45Co1.45Cu0.1O4 spinel can therefore be considered a suitable material for a coating on the Crofer 22 H ferritic steel, with intermediate-temperature solid oxide electrolyzer cells as the target application.

关键词： Ethyl cellulose   Bentonite   Composite film   Structure and surface morphology   Tensile strength   Adsorption   Methylene blue  

摘要： Ethyl cellulose (EC) was filled with bentonite (Bent) particles by mechanical dispersion to produce composite film materials that were studied using various methods. According to X-ray diffraction (XRD) analysis, the inter-chain separation length was larger in EC/Bent composite then those in pure polymer. Infrared spectrometry indicated a formation of hydrogen bonds between the hydroxyl groups of EC and the silanol groups of clay. Tests showed an increase in tensile strength of the polymer material (by 35-40%) when doped with bentonite. It was found that modification of polymer with bentonite resulted in increasing of the adsorption efficiency of methylene blue (MB): the equilibrium concentration of MB ions in adsorbent phase increased 2.5 times. The MB adsorption kinetics obeyed the pseudo-first-order mechanism. Isotherms were in good agreement with Langmuir model. For the composite, the maximum monolayer adsorption capacity was 4 times higher than that for pure polymer.

关键词： Emulsion   Freeze-drying   Oleogel   Polymer   Vacuum-drying  

摘要： In current study, oleogel containing surface-active (sodium caseinate) and non-surface active biopolymers (xanthan gum) prepared in different concentrations through emulsion template (containing 60% canola oil) and dried by freeze-drying. Results showed that biopolymer content affects the oleogel structure: applying the biopolymer combination with increased concentration mainly sodium caseinate, resulted in lower droplet size in emulsions and obtained oleogels with higher firmness and less oil loss. Therefore, samples containing 4% sodium caseinate with 0.2% and 0.4% xanthan were selected as the superior formulas for examining deeply the drying methods' effects (freeze and vacuum-oven drying) on oleogel's physicochemical properties such as hardness, rheology, XRD, color, and oxidative stability. Freeze-drying with higher content of xanthan (0.4% w/w) generated a high mechanical strength oleogel. However, reducing xanthan concentration (0.2% w/w) reduced the gel strength, probably due to not enough viscoelasticity in oil droplets interface. Nevertheless, the charm of freeze-drying method is high-quality dried products in optimized biopolymer concentration due to the water removal by sublimation of ice crystals. Contrariwise, vacuum-oven revealed soft-discolored materials even in high biopolymers concentrations due to the higher temperature and structural collapse. Independence of biopolymer concentration and drying method, no significant difference in XRD patterns, and oxidative stability was observed.

关键词： Polyurethane foam   Thermal aging   Seawater aging   SEM microstructure   Glass transition temperature   Mechanical properties  

摘要： The purpose of this study was the identification of qualitative and quantitative changes in the visual appearance, chemical structure, morphology and selected physicochemical and mechanical properties of the closed cell rigid PU foam while heated in air and seawater for predicting its performance and durability. Specimens were aged at constant temperatures of 40 and 80 degrees C for a period of 10 weeks. Aging caused a yellowing of the samples. Scanning electron microscopy (SEM) revealed that foam pores lost their regularity. Differential scanning calorimetry (DSC) showed that the glass transition temperature (T-g) increased on average by 15 and 80%, respectively for samples heated at 40 and 80 degrees C. Water absorption (WS) also increased over time, respectively, by a maximum of 15 and 25%. The flexural strength (sigma(flex)) and compressive (sigma(comp)) strength showed a decreasing tendency, whereas for tensile strength (sigma(tens)), an increase was observed. The starting material was characterized by the sigma(flex), sigma(tens) and sigma(comp) of: 436, 413 and 284 kPa, respectively. The lowest determined sigma(flex) value was of 345 kPa, and sigma(comp) value was of 158 kPa. The highest determined sigma(tens) equaled to 608 kPa, respectively. The changes in flexural modulus were statistically insignificant and its average value was of 4.0 MPa.

关键词： Oat   Pea   beta-Glucan   Protein isolate   Meat analogues   High-moisture extrusion  

摘要： A new generation of plant-based texturized meat analogues attempts to boost the consumption of dietary fiber. In the present study, oat fiber concentrate (OFC) and pea protein isolate (PPI) were combined (30:70;50:50;70:30) and processed with high-moisture extrusion (long cooling die temperature [LCDT]: 40, 60 and 80 degrees C;screw speed [SS]: 300, 400 and 500 rpm) to obtain meat-mimicking fibrous meat analogues (FMAs). The results showed that OFC reduced the structural strength (e.g., hardness, chewiness) of the FMAs, whereas LCDT strengthened the structure. Micmtomography imaging revealed that FMAs containing more OFC presented smaller void thickness, thus reducing the FMAs' water holding capacity. An in-vitro gastrointestinal model showed that the extractability and viscosity of p-glucan were well preserved, particularly at low LCDT. Overall, it was possible to add substantial amounts of OFC (30-50%) to FMAs while maintaining fibrous meat-mimicking structures and retaining the oat fiber's viscous properties.