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关键词： Wheat gluten   NaCl   Extrusion   Meat analogues  

摘要： The study focused on the effect of different concentrations of sodium chloride (0%, 0.5%, 1%, 3%, 5%, and 10%;NaCl) on the physicochemical and structural properties, including texture properties, protein polymerization, rheological properties and morphology formation, of extruded wheat gluten. The hardness, chewiness, and resilience of the extrudates were increased by NaCl. The highest value of the degree of texturization was obtained at 3%, but decreased at 5% and 10%. The extrudates exhibited lower bulk density and darker colour when NaCl was added. The sodium dodecyl sulfate (SDS)-soluble protein polymers exhibited a similar trend and the lowest value was obtained at 3% addition, which indicated the highest degree of aggregation. The addition of NaCl (0.5%-3%) showed positive effect on the oxidation of sulfhydryl groups to disulfide bonds. The content of beta-sheets showed an increase tendency at 0.5%-3% NaCl addition. The addition of NaCl increased the storage and loss modulus in wheat gluten dough while decreasing that of the extrudates. Microstructure analysis by light microscopy and SEM confirmed that the fibrous structure was enhanced with increasing levels of NaCl, and the 3% treatment showed the best, but that collapsed at 5% and 10% NaCl concentrations.

关键词： Cooking loss   Texture   Microstructure   Dynamic rheological properties   Apparent viscosity  

摘要： This study was aimed to investigate the effects of ultrasound, basic amino acids (l-lysine and l-arginine), and their combination treatments on the physicochemical properties of emulsion sausages and raw meat batters. A combination of ultrasonic and l-lysine treatment resulted in 69.8% decrease in cooking loss, 70.6% decrease in total expressible fluids, 11.1% decrease in expressible fat in sausages as compared to those with ultrasonic treatment;and 15.7% reduction in cooking loss, 18.8% reduction in total expressible fluids and 6.8% reduction in expressible fat in sausages as compared to those with l-lysine treatments, respectively. Similarly, a combination of ultrasonic and l-arginine treatment led to 91.9% decrease in cooking loss, 89.5% decrease in total expressible fluids, 27.1% decrease in expressible fat in sausages as compared to those with ultrasonic treatment;and 48.3% reduction in cooking loss, 43.9% reduction in total expressible fluids and 14.9% reduction in expressible fat in sausages as compared to those with l-arginine treatment, respectively. Meanwhile, their combination treatments were more effective than their individual treatments in improving textural properties. Confocal laser scanning microscopy revealed that the emulsion sausages treated with a combination of ultrasound and l-lysine/l-arginine exhibited smaller and more uniform fat/oil droplets, compared to the emulsion sausages treated with ultrasound, l-lysine, or l-arginine, respectively. l-Lysine/l-arginine treatments could lead to changes in the rheological pattern of meat batters, while ultrasonic treatment could not. Nevertheless, ultrasonic treatment resulted in increase in the storage modulus and apparent viscosity of meat batter regardless of l-lysine/l-arginine in most cases. Summarily, ultrasound could assist l-lysine/l-arginine to improve the quality characteristics of emulsion sausage.

关键词： Microwave hydrothermal   TiO2 nanostructure   Photocatalyst   NOx gas  

摘要： TiO2 nanostructures have been prepared via microwave hydrothermal process using different NaOH concentrations. The physicochemical properties of the products were systematically investigated by using UV-vis Diffuse Reflectance Spectra, X-ray Photoelectron Spectra, Photoluminescence Spectra, Raman, N-2 adsorptiondesorption, and Transmission Electron Microscope analysis. The results indicated a close correlation between the NaOH concentration and different types of nanostructured titania products obtained from the microwaveassisted hydrothermal process. At low NaOH concentrations (4 M and 6 M), the precursor TiO2 nanoparticles partially converted into a mixture of one dimensional (1D) nanostructures (e.g., nanorods or nanowires) and 2D nanostructures such as nanosheets. As the NaOH concentration is increased to 8 M and 10 M, the obtained TiO2 products contain nanosheet and nanotube-like structures, respectively, with a significantly larger specific surface area. The photocatalytic performance of the synthesized TiO2 products, prepared under different NaOH concentrations, were evaluated through the toxic NOx gas removal efficiencies. The nanostructured TiO2 samples prepared at a higher NaOH concentration have shown improved de-NOx efficiencies than the TiO2-P25 precursor.

关键词： Physicochemical properties  

摘要： Abstract: A comparative analysis of the physicochemical properties of ethoxylated derivatives of normal decyl alcohol ODAn and ethoxylated derivatives of isononylphenol ONPn, which are nonionogenic surfactants, is presented. The molecular-kinetic features of the fast and ultrafast stages of restructuring of ODAn and ONPn are analyzed. © 2021, Pleiades Publishing, Ltd.

关键词： Deep frying   Vegetable oil   Physicochemical properties   Heating time  

摘要： The determination of oil physicochemical properties is a useful strategy to monitor oil quality to avoid the use of potentially toxic oil. It is relevant in determining the physical and chemical changes that oil undergo during heating. In this work, the effect of prolong heating time from 1-7 h on the physicochemical properties of soybean oil, palmolein oil, groundnut oil and palm kernel oil was examined. Properties such as specific gravity, viscosity, saponification value (SV), iodine value (IV), free fatty acid and peroxide value (PV) were studied to evaluate the compositional quality of oils. Results revealed that heating at the different times did not have any significant effect on the physicochemical properties of the oils. There was however, significant differences of the physicochemical properties on the oil types. Results further reveal that based on the peroxide value, soybean oil was the most stable oil out of the four oils studied while palm kernel oil was found to be the least stable oil;as the stability of palm olein oil was found greater than that of groundnut oil. (C) 2021 Published by Elsevier B.V. on behalf of King Saud University.

关键词： Active food packaging   Essential oils   Electrospinning   Antimicrobial packaging   Food quality   Nanotechnology  

摘要： Recently, combination of nanotechnology and active food packaging provided new horizon to extend the shelf life of food. This study aimed to fabricate natural nanofibrous film incorporated with essential oils using the nanospinning technique and examine its antimicrobial activity. Constituents of Zataria multiflora and Cinnamon zeylanicum essential oils (EOs) were investigated by Gas Chromatography-Mass Spectrometry and their antimicrobial properties were examined. Subsequently, electrospun Soy Protein Isolate (SPI)/Gelatin was embedded with Zataria multiflora and Cinnamon zeylanicum EOs. Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectrometry (FTIR), and Thermogravimetric analysis (TGA) were done to evaluate the properties of electrospun fibers. The antimicrobial activity of nanofibrous films was evaluated. SEM revealed that the addition of 30% gelatin neutralized SPI charge, representing a significant increase in the diameter of nanofibers by 314.08 nm. Furthermore, TGA showed stability for Soy/Gel nanofibers. The fabricated nanofibrous film exhibited exquisite antimicrobial activity against Gram-negative and Gram-positive pathogens. For example, SPI-gelatin nanofibrous film incorporated with 20% Z. multiflora reduced 100% of S. aureus, B. cereus, and ***. The reduction for E. coli and S. typhimurium were 70% and 63%, respectively. We suggest that incorporating EOs with nanofibrous films can be a promising method to extend the shelf life of food and can be used in production for active food packaging.

关键词： Centrifugation  

摘要： Pasteurized liquid whole egg was fractionated by centrifugation. Several studies showed the composition of plasma and granules that can be obtained by egg yolk centrifugation. However, few studies deal about liquid whole egg fractionation. In this work, the effect of operational conditions (relative centrifugal force-RCF, time, and temperature) on the physicochemical quality of plasma and granules was evaluated. These fractions were compared with liquid whole egg as control. The physicochemical parameters analyzed were fractionation yield and ratio, pH, water activity (a(w)), and color (L*, a*, b*, chroma, and hue). The plasma yield obtained ranged from 75.10% to 84.44% while the granule yield varied from 8.16% to 15.00%. Equations to forecast fractionation yield and ratio were developed. For example, the best conditions for high plasma recovery are 8,000 g for 10 min at 4 degrees C;where the P/G ratio and plasma yield estimated are 91.08% and 84.64%, respectively. While only a granule yield of 7.88% is expected. Prediction models were also obtained for pH and color. No significant differences were detected for a(w). However, significant differences were detected in color between whole egg, plasma, and granules. Practical applications This work provides a database and equations that could be used for the fractionation by centrifugation of liquid whole egg to obtain new products with improved functional properties.

关键词： Quinoa   Starch   Dry heat treatment   Physicochemical properties   Structural properties  

摘要： Repeated and continuous dry heat treatment (RDHT and CDHT, respectively) are new methods for starch modification. RDHT and CDHT were applied to quinoa starch, and their effects on its physicochemical, structural properties and in vitro digestibility of quinoa starch were determined. The results showed that the crystal type of quinoa starch was not change and remained A-type after dry heat treatments. After dry heat treatments, the relative crystallinity, water-solubility, and the pasting parameters of quinoa starch increased, while the swelling power decreased. Relative crystallinity, water absorption index, and percentage of rapidly digestible starch were significantly higher in RDHT starch samples than CDHT starch samples for the same duration. The variation in the infrared absorbance ratio of 1032 cm(-1) and 1013 cm(-1) was higher for RDHT starch samples than for CDHT starch samples, consistent with their relative crystallinity. Compared with CDHT starch samples, RDHT starch samples showed lower water solubility, swelling power, paste viscosity and thermal parameter values (To, Tp, Tc, Delta T). On the whole, RDHT showed better performance for altering the physicochemical and structural properties of quinoa starch compared with CDHT. DHT can increase the solubility of quinoa starch, and DHT starch with higher peak viscosity can be used as thickener in food.

关键词： Functional properties   Pearl millet cultivars (ashana   demby)   Morphological properties   Pepsin   Starch yield  

摘要： Influence of enzymatic and SO2 treatments on the yield, physicochemical, functional, morphological, and colour properties of starches isolated from pearl millet (Ashana and Demby cultivars) was studied. The treatment conditions were;control (steeping for 24 h with 0.2% SO2), B (steeping for 7 h with 3 h in distilled water and 4 h in 0.1 M sodium acetate buffer pH, 4.5), S (steeping for 7 h with 3 h in distilled water and 4 h in 0.2% SO2), BE (steeping for 7 h with 3 h in distilled water and 4 h in 0.1 M sodium acetate buffer pH (4-4.5) + 250 mg pepsin) and BES (steeping for 7 h with 3 h in distilled water and 4 h in 0.1 M sodium acetate buffer pH, 4.5, + 250 mg pepsin + 0.2% SO2). The result showed that starch yield from the treatment BE, BES and S was significantly (p <= 0.05) higher than that of B and control treatments in both cultivars. From the micrographs studies, the hydrolytic effect of pepsin on protein matrix attached to the starch could be observed as holes created on the surface of starch granules. All treatments significantly (p <= 0.05) affected the amylose content and pH value of both starches, while the falling number and acidity were not affected (p >= 0.05) by these treatments compared to controls. Water absorption capacity and fat absorption capacity reduced significantly in all treated starches from the two pearl millet cultivars, while viscosity increased following treatments in both cultivars except treatment S (p <= 0.01). In conclusion, functional properties and yield of starch from both millet cultivars were improved by using a combination of enzyme and SO2 during wet milling process.

关键词： Polyethylene terephthalate   CI Disperse Red 167   Supercritical fluid   Tensile strength   Crystallinity   Orientation  

摘要： The effects of supercritical CO2 and C.I. Disperse Red 167 as media on the structural and chemical properties of polyethylene terephthalate (PET) fibers were observed in the supercritical dyeing process of these fibers using numerous methods to predict changes in their physical properties. PET samples were classified into three cases based on the sample preparation and analysis steps. When the PET fibers were treated without C.I. Disperse Red 167 under a supercritical fluid CO2 solvent at 120 degrees C and 25 MPa, their crystallinity, orientation, and tensile strength decreased the most among the three cases, whereas when they were treated with C.I. Disperse Red 167 under the same conditions, the three above-mentioned characteristics were relatively improved compared to the scenario without the C.I. Disperse Red 167 treatment. These experimental results provided significant information on the effects of supercritical CO(2 )and C.I. Disperse Red 167 on the properties of PET fiber polymers.