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关键词： Tensile strength  

摘要： Films were obtained by casting a solution of succinated hydrolyzed corn starch homogenized using an ULTRA-TURRAX (UF). Glycerol was added as a plasticizer. Films obtained after homogenizing with a magnetic bar by the conventional method (CF) were used as a control. The physicochemical, thermomechanical, and hygroscopic properties were evaluated. UF resulted in a gray color change when heating at 65 degrees C during the mechanical homogenization process, while the CF remained white. The thermomechanical properties depended on the conditioning at different relative humidity values. Mechanical properties of the UF showed the lowest values of tensile strength (TS) and percentage of elongation (%E). The mechanical homogenization at high revolutions allowed changing the physicochemical and mechanical properties of the films obtained from dual modified starch, probably due to the dispersion, rearrangement, orientation, and interaction of the macromolecular components of the modified polymers. These films could have a wide array of applications. Practical applications These films have a wide array of applications in foods with low moisture content. Also providing new information for future research using doubly modified starch by homogenizing it at high revolutions, causing new molecular interactions and eventually physicochemical properties new.

关键词： Conducting polymer   Carbazole   Electrodeposition   Atomic force microscopy   Stiffness  

摘要： The polymerization of carbazole (Cz) and N-((methoxycarbonyl)methyl)carbazole (CzE) was carried out by electrochemical oxidation in acetonitrile solution. Different feed ratios of monomers were used to deposit polymer thin films with different compositions and study the influence of the ratio of monomers on the electrochemical, morphological, mechanical and adhesive properties of the polymer films. The electrochemical oxidation led to the deposition of a polymer film whatever the feed ratio but the thickness of the film increased with the portion of unmodified carbazole. On the contrary, the composition of the monomer mixture had a low influence on the AFM adhesion forces between the AFM tip and the polymer film. Depending on the feed monomer ratio, the morphology was either globular or columnar (when the portion of CzE was comprised between 10% and 70%). The stiffness of the polymer films was also found to be strongly dependent on the feed ratio since it varied from 2 to 115 GPa depending on the monomer ratio. The polymer films prepared from the ratios 90:10 and 70:30 in Cz:CzE monomer solutions were found to be the most interesting ones since they led to thick and conducting polymer films with a good adhesion and a low stiffness. Moreover, these coatings were uniform and exhibited an original columnar structure.

关键词： hydrochemistry   groundwater   drinking water   upscaling   multivariate analysis   mapping  

摘要： In France, the data resulting from monitoring water intended for human consumption are integrated into a national database called SISE-Eaux, a useful and relevant tool for studying the quality of raw and distributed water. A previous study carried out on all the data from the Provence-Alpes-Cote d'Azur (PACA) region in south-eastern France (1061 sampling points, 5295 analyses and 15 parameters) revealed that the dilution of the information in a heterogeneous environment constitutes an obstacle to the analysis of ongoing processes that are sources of variability. In this article, cross-referencing this information with the compartmentalization into groundwater bodies (MESO) provides a hydrogeological constraint on the dataset that can help to better define more homogeneous subsets and improve the interpretation. The approach involves three steps: (1) A principal component analysis conducted on the whole dataset aimed at eliminating information redundancy;(2) an unsupervised grouping of groundwater bodies having similar sources of variability;(3) a principal component analysis carried out within the main groups and sub-groups identified, aiming to define and prioritize the sources of variability and the associated processes. The results supported by discriminant analysis and machine learning show that the grouping of MESO is the best-suited scale to study ongoing processes due to greater homogeneity. One of the eight main groups identified in PACA, corresponding to the accompanying aquifers of the main rivers, is analyzed by way of illustration. Water-rock interactions, redox processes and their effects on the release of metals, arsenic and fecal contamination along different pathways were specifically identified with varying impacts according to the subgroups. We discussed both the significance of the principal components and the mean values of the bacteriological parameters, which provide information on the causes and on the state of contamination, respectively. Bas

关键词： Gelatin   Tilapia   Temperature   Emulsion   Rheology  

摘要： This study investigated the influence of thermal treatment (30 degrees C to 110 degrees C, 30 min) on the physicochemical and rheological properties of an emulsion stabilized by black tilapia (Oreochromis mossambicus) skin at pH 4. The protein pattern of tilapia gelatin did not have any significant difference after the gelatin was heated within a temperature range of 30 degrees C to 70 degrees C. However, at 90 degrees C and 110 degrees C, denaturation occurred where alpha-, beta- and gamma-chains of the gelatin were degraded, leading to a concomitant increase in low molecular peptides. The emulsion stability was investigated through a particle size analyzer, zeta potential, microscopic observation and creaming index. The gelatin emulsion was physically stable at 30 degrees C to 70 degrees C with a mean droplet size of less than 13 mu m. When the heating temperature was increased to 90 degrees C and 110 degrees C, the emulsion showed a pronounced increase in droplet size due to coalescence. The gelatin emulsion heated at 90 degrees C and 110 degrees C also displayed instability against creaming after storage at room temperature for 7 days. As the heating temperature increased, the gelatin emulsion exhibited a decrease in apparent viscosity and the flow behavior changed from shear thinning to Newtonian. The rheological data also showed that the storage modulus (G ') of emulsion became more frequency dependent as the heating temperature increased, indicating weak droplet interactions. The tilapia gelatin emulsion was physically unstable when subjected to thermal treatment above 70 degrees C. The data reported in this study provides useful insight into the formulation of acidic food emulsions that require thermal treatment.

关键词： Rise husk   Silicon dioxide   Silica   Biogenic   Wasteless technology   High-purity  

摘要： Plant-based biogenic silicon dioxide nanoparticles are used to produce catalysts, additives, templates for deposition of other semiconductors and metals, nanomaterials with novel properties, bio-nanocomposites for biomedical, energy and environmental fields. There are too many ways of bio-SiO2 production. Dependent on the way and obtaining condition some properties of the plant-based biogenic silicon dioxide nanoparticles can be changed. The most amount of silicon is accumulated in stalks and husk biomass of rice, buckwheat and oats. The aim of our work was the investigation of physic-chemical properties of the biogenic silicon dioxide obtained from the rice husk by both ecologically- and economically-friendly technology. The fluoric technology was used for silicon dioxide isolation. Our technology allows us to restore used catalysts. Thus this technology is ecologically and economically efficient. The synthesised SiO2 was studied by using the following methods: low-temperature nitrogen sorption-desorption, XRD, XRF, ICP-MS, AFM, FTIR-ATR, SEM-EDS, TGA. It was established that obtained samples had a specific surface area 107 m(2)/g. The XRD of the powdered SiO2 showed 100% amorphous characteristics of the material. FTIR, XRF SEM-EDS, ICP-MS and X-ray diffraction indicated that samples contain only SiO2. AFM results show obtained silica particles were having shape from spherical to lamellar. According to SEM investigated sample consists of spherical small aggregates.

关键词： Phthalocyanine   Nanoconjugate   Fluorescence   Singlet oxygen   Triplet   Nonlinear optics  

摘要： Phthalocyanine (Pc) complexes are an important class of dyes with numerous (e.g., biological, photophysical, and analytical) applications. Among the methods used to improve the properties of these complexes, one should mention the introduction of different substituents, variation of the central metal ion, ligand exchange, and conjugation to nanomaterials (e.g., carbon-based nanomaterials and metal nanoparticles (NPs)). This work briefly reviews Pc complex conjugation to Ag and Au NPs, highlights the different NP shapes, and discusses the diversity of conjugation approaches. Moreover, the use of UV-Vis spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, atomic force microscopy, dynamic light scattering and Fourier transform infrared spectroscopy to characterize Pc-NP hybrids is summarized. The effect of conjugation on Pc photo-physicochemical properties (fluorescence, singlet oxygen generation, triplet state formation, and optical limiting behavior) is discussed, and future perspectives for the synthesis and applications of new hybrids are provided. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.

关键词： lupin   vegan foods   functional foods   fermentation   kefir   lactic acid bacteria   yeast   antioxidants   free radicals scavenging  

摘要： Plant derived fermented beverages have recently gained consumers' interest, particularly due to their intrinsic functional properties and presence of beneficial microorganisms. Three variants containing 5%, 10%, and 15% (w/w) of sweet blue lupin (Lupinus angustifolius L. cv. "Boregine") seeds were inoculated with kefir grains and incubated at 25 degrees C for 24 h. After processing, beverages were stored in refrigerated conditions (6 degrees C) for 21 days. Changes in microbial population, pH, bioactive compounds (polyphenolics, flavonoids, ascorbic acid), reducing sugars, and free amino acids were estimated. Additionally, viscosity, firmness, color, and free radicals scavenging properties were determined. Results showed that lactic acid bacteria as well as yeast were capable of growing well in the lupin matrix without any supplementation. During the process of refrigeration, the viability of the microorganisms was over the recommended minimum level for kefir products. Hydrolysis of polysaccharides as well as increase of free amino acids was observed. As a result of fermentation, the beverages showed excellent DPPH, ABTS(+center dot), (OH)-O-center dot, and O-2(-) radicals scavenging activities with a potential when considering diseases associated with oxidative stress. This beverages could be used as a new, non-dairy vehicle for beneficial microflora consumption, especially by vegans and lactose-intolerant consumers.

关键词： Fruits  

摘要： Fruit yoghurt with tulsi enhance the nutritional value and satisfy rising demands for healthy food products. Three different concentrations of TLE (0.5%, 1%, and 1.5%);and apple pulp (10%) were used for the formulation of herbal fruit yoghurt. The enriched milk (26.42-28.58 min) showed lower heat stability than that of control (29.80 min), however, sufficient to withstand sterilization treatment up to 1% TLE addition. Furthermore, physicochemical properties viz. pH, water holding capacity, acidity, moisture, water activity, setting time, and whey-off experiment were not affected significantly (p > .05) in comparison to control yoghurt. The tulsi addition significantly (p < .05) increased (from 32.43% to 45.47% inhibition) the antioxidant activity of yoghurt. The firmness of herbal fruit yoghurt was decreased than control yoghurt. Sensory scores were decreased with an increase in the concentration of TLE (88.75 to 85.14) in comparison to control (91.96), however, yoghurt was suitable for consumption up to 1% TLE. Practical applications Dahi, Tulsi, and fruit mix are considered as religious food and known as Panchamrite. Yoghurt is considered as western dahi in India, however, no such mixture is tried with yoghurt. Therefore, the feasibility of yoghurt with tulsi and apple was carried out, as yoghurt has higher health benefits even than tulsi. A good quality yoghurt was developed using tulsi and apple pulp, therefore, it will capture a huge place in the Indian market.

关键词： Pacific oyster   Heat treatment   Denaturation   Aggregation   In vitro digestion  

摘要： The current research extracted oyster salt-soluble protein (OSSP) from Pacific oyster (Crassostrea gigas) and investigated the effect of heat treatment (35-100 degrees C) on the physicochemical state and in vitro digestion of OSSP. Gel electrophoresis results indicated that OSSP was mainly composed of myofibrillar proteins. The denaturation temperature and enthalpy of OSSP were 54.88 degrees C and 5.49 J/g, respectively. Heating resulted in significantly decreased protein solubility and increased surface hydrophobicity and carbonyl content of OSSP (P < 0.05). Meanwhile protein oxidation and increasing surface hydrophobicity led to the change of OSSP aggregation state. The results of in vitro digestion showed that the digestion of OSSP was inhibited by protein oxidation and aggregation. However, this inhibition was only reflected in protein content, but not in molecular weight distribution. Proteome analysis indicated that identified peptides mainly came from myosin heavy chain striated muscle, paramyosin and tropomyosin, and the types of peptides were determined by OSSP amino acids composition.

关键词： Insoluble soy peptide aggregate   Modification   Physicochemical properties   Interfacial properties   Emulsions  

摘要： The physicochemical, interfacial and emulsifying properties of insoluble soy peptide aggregate (ISPA) modified by homogenization and alkaline-treatment (pH10, pH12) were studied in this paper. Homogenization and alkaline-treatment improved the content of hydrophobic amino acids of ISPA, promoting the surface hydro-phobicity (H-0), decreasing the hydrodynamic diameter (D-H) and zeta-potential, finally enhanced the solubility and oil holding capacity (OHC). Compared to ISPA modified at pH10, ISPA modified at pH12 exhibited lower interfacial pressure (pi) but higher viscoelastic modulus (E). Emulsions stabilized by modified ISPA had lower zeta-potential, smaller d(4,3) and flocculation index (FI), and better stability than untreated ISPA. It was noticed that homogenization pretreatment had a synergistic effect with alkaline treatment on the improvement of emulsifying property. The effects of pH12 on the physicochemical properties of ISPA were more significant than pH10 possibly referred to the disrupting of intramolecular interaction, showing better solubility and emulsifying property. In summary, the emulsifying properties of modified ISPA were even better than that of commercial SPI, indicating that ISPA has the potential to be a good emulsifier in food industry.