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关键词： Blue corn   Black bean   Anthocyanins   Third-generation snacks   Optimization   Extrusion cooking process   Microwave expanded  

摘要： The effects of extrusion on the physicochemical properties of a mixture of blue corn, black bean, and sweet chard (MBBC) used for indirectly extruded snacks (PECB) and microwave-expanded snacks (MEPM) were evaluated. MBBC was conditioned at moisture content (MC) of 22.2-35.7%, extruded at temperature (ET) of 102-142 degrees C, and screw speed (SP) in the range of 96-171 rpm. The water absorption index (WAI), water solubility index (WSI), expansion index (EI), final viscosity (FV), setback values, total anthocyanin (TAC), hardness, FT-IR, X-ray analysis, and microstructure were evaluated. TAC increased with the reduction of ET of PECB and MEPM. Reductions in MC and increases in SP caused an increase in EI, WAI, and WSI, while PV and setback values showed contrasting behaviors. Micrographs revealed that extrusion destroys the granular structure of starch EMCBgenerated. FT-IR showed that extruded samples increased the intensity of bands at 994 and 1016 cm 1 in comparison to raw starch, and can be observed V-type diffraction pattern. The predicted optimal conditions were obtained at 133 rpm, 25% MC, and 122 degrees C. Under these conditions, extruded products had greater retention of anthocyanins (34%) with adequate rheological parameters, which resulted in a maximum expansion of the extrudates.

关键词： Glycolytic oscillations   Association-induction hypothesis   Membrane theory   Colloidal systems   Intracellular water  

摘要： Important concepts from colloidal physical chemistry such as coacervation, phase transitions, emergent properties and ionic association, are currently emerging in the lexicon of cellular biology, prompted mostly by recent experimental observations of liquid phase coexistence in the cell cytosol. Nevertheless, from an historical point of view, the application of these concepts in cell biology is not new. They were key concepts into the so-called protoplasmic doctrine, an alternative (and largely forgotten) approach to cell physiology. The most complete theory originating from this line of thinking was the Association-Induction Hypothesis (AIH), introduced by Gilbert N. Ling in 1962. The AIH, which envisions living cells as complex dynamical colloidal systems, provides ample theory and experimental evidence to call into question the now dominant view of living cells as fluid-filled vesicles. This review attempts to present and discuss the usefulness of the AIH to understand a series of experimental observations from our laboratory from living suspensions of the yeast Saccharomyces cerevisiae exhibiting glycolytic oscil-lations. Particularly, the AIH helped us integrate, in a mechanistic sense, the basis of a strong temporal coupling observed between ATP and a series of cellular properties such as intracellular water dipolar relaxation, intracellular K+ concentration, among many others, where the colloidal physical chemistry of the cell interior plays a fundamental role. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Clay minerals   Characterization   Kaolin   Oued Ziz   Fe-57 Mö   ssbauer spectrometry  

摘要： A new source of clay mineral was explored and an extraction and purification protocol was developed to isolate it from raw clay samples acquired in the Oued Ziz region of southeastern Morocco. Clay minerals are always identified in the raw clay or soil by a purification step, as the presence of carbonates, iron oxides or organic matter interferes with the identification process. Purification is also necessary to study the properties of clay minerals. The process involved the collection of raw clay from the source, as well as mineralogical, and physicochemical characterizations. Characterization of the prepared materials was done using X-ray diffraction spectrometry (XRD) which makes it possible to determine the structure and nature of clay. The basic chemical analysis of the materials was carried out by X-ray fluorescence (XRF) and inductively coupled plasma-Atomic emission spectroscopy (ICP-AES). Moreover, Energy dispersive X-ray analysis (EDX) and Fourier transform-infrared spectroscopy (FT-IR Spectroscopy) were used to investigate the chemical composition or nature of minerals. The morphology of the clay samples is unveiled by scanning electron microscopy (SEM), thus thermal analysis (TGA-DTA) records the sample mass loss caused by thermal transformations such as dehydration or calcination for clay minerals. Fe-57 Mossbauer spectrometry was also used to investigate the presence of iron in clay samples.

关键词： Fibers   Texture profile   Sensorial analysis   Multivariate analysis   Univariate analysis  

摘要： This work aimed to prepare a chicken hamburger by adding biomass and using chemometrics as a tool to evaluate physical, physicochemical, sensory, and technological properties. Green banana (GB) and passion fruit epicarp (PFE) biomasses were characterized by granulometry, water activity, moisture, and color. Four hamburger formulations have been developed using different compositions of those biomasses: no biomass addition (control);10% of GB;10% of PFE;and 5% of each biomass, and characterized in terms of physical and physicochemical analysis, technological properties, texture profile, and sensory analysis. The production of hamburgers with 10% GB is an alternative to enrich and maintain their physicochemical and physical parameters, besides their technological properties. The improvement in texture may be analysed as the major benefits, making better parameters such as firmness, gumminess, and chewability. Moreover, the results obtained by univariate and multivariate statistical analysis highlighted the importance of using different mathematical approaches, which complemented each other and provided extensive information about the hamburgers.

关键词： Eggs   Egg hairs (setae)   Morphology   Physico-chemical characterization   Spodoptera frugiperda  

摘要： In this study, we report first time in India on the morphology, ultra-architectural pattern of the chorion in the egg and egg hair (setae). Further, physico-chemical characterizations of egg hairs (setae) were studied in the new invasive pest, fall armyworm, Spodoptera frugiperda. The egg is dome shaped with flattened base and curves upward to a broadly rounded point at the apex. HR-SEM micrographs revealed the surface ultrastructure of eggs chorion and shows structural elements of a marked rosette of petals surround the micropyle followed by micropylar rosette region around the micropyle plate. There was a small single micropylar opening along with 9 micropylar rosette cells and 13 micropylar rosette zones present near to the micropylar pit. In the egg the first order ribs were absent, but around 58-60 numbers of second order ribs were present. All the ventral and lateral cells of the eggs are connected by 19-22 cross striae and not forming a grid pattern, but joints with the longitudinal ribs at several of angles and totally 1,277-1,495 convex cells present at the egg's surface. The physico-chemical characteristics of egg hairs were studied using Fourier transform infrared (FT-IR) and thermogravimetric analysis (TGA) analysis. TGA results show that three weight losses occurred at 142, 418, and 880 degrees C, respectively. FT-IR confirms the presence of amides, sulfoxide, and nitro compounds in egg hairs (setae).

关键词： Atmospheric pressure  

摘要： Changes in water state, glass-transition temperature (T-g), microstructure, and some quality attributes of preserved kumquats after osmotic dehydration under atmospheric pressure or vacuum conditions followed by hot-air drying were investigated. Low-field nuclear magnetic resonance results showed that there was less immobilized water content in kumquats under vacuum impregnation with sugar (VSKs) versus that of kumquats under atmospheric pressure osmosis with sugar (ASKs). The freedom of water in kumquats under atmospheric pressure osmosis with sugar and then hot air-drying (VS-ADKs) was lower than that of kumquats under vacuum osmosis with sugar and then hot air-drying (AS-ADKs). Magnetic resonance imaging results revealed the water release. Sucrose intake produced a more pronounced depressing influence on the T-g of VSKs than on that of the T-g of ASKs. The T-g of VS-ADKs were lower than that of AS-ADKs. Scanning electron microscopy displayed that the VSKs samples presented relatively compact tissue, but the ASKs exhibited the rupture of the cell cavities. The VS-ADKs showed the more compact lamellar structure but the AS-ADKs showed more loose fragments. The lightness of color in VSKs significantly decreased, while the redness and yellowness in ASKs diminished. High hardness and gumminess values were identified in VSKs and VS-ADKs. Correlation analyses showed that hardness was positively correlated with T-23 either in the ASKs or in the VSKs. Practical Application Changes in water state, glass-transition temperature (T-g), microstructure, and some quality attributes of preserved kumquats after osmotic dehydration under atmospheric pressure or vacuum conditions followed by hot-air drying were investigated. Low-field nuclear magnetic resonance, magnetic resonance imaging, differential scanning calorimetry, scanning electron microscopy and so on were used as the intuitive and efficient methods. The differences in two immerse methods and the effects of drying on the p

关键词： Triticum durum L   landraces   gluten strength   rheological methods   technological parameters   bread‐   making  

摘要： The efficacy of empirical rheological methodology for modern Triticum aestivum L. in predicting bread-making quality in Triticum turgidum L. ssp. durum is warranting of attention. The present study was aimed at providing a comparative evaluation of an array of standard rheological tests in predicting bread quality in three modern cultivars (Core, Sant'Agata and Simeto) and three durum wheat landraces (Rusca, Timila and Tumminia SG3). Gluten strength, alveograph dough strength and tenacity/extensibility ratio, farinograph stability and mixograph peak dough height and overall score, were significantly higher in the modern cultivars, and distinctive in accounting for the variance between modern and old genotypes, using principal component analysis. Quality bread-making parameters, including bread volume, height and specific volume, were significantly higher in the durum wheat landraces. Standard rheological parameters were ineffective in predicting bread quality, necessitating the requisite in redefining rheological parameters to meet the increasing interest in heritage durum wheat genotypes for bread-making.

关键词： cluster   rhenium   organic ligands   crystal structure   electronic structure  

摘要： Four novel rhenium cluster complexes with the general formula trans-[Re(6)Q(8)(ppy)(4)X-2]center dot n(ppy) (Q = S, Se;X = Cl, Br;ppy = 4-phenylpyridine) are obtained by the interaction of salts Cs-n[Re(6)Q(8)X(6)]center dot 2H(2)O (Q = S, n = 4;Q = Se, n = 3;X = Cl or Br) with a 4-phenylpyridine melt. The single-crystal XRD study shows that the structures of these compounds contain molecular fragments trans-[Re(6)Q(8)(ppy)(4)X-2] packed together with 4-phenylpyridine solvate molecules and connected with these molecules by weak interactions, including hydrogen bonds and pi-stacking of aromatic rings. It is shown that different halide and chalcogenide ligands of the cluster complex form different types of packing. The obtained compounds are insoluble in water and in organic solvents. The crystal samples are luminescent in the red region with emission peaks at 708-718 nm, quantum yields of 0.01-0.03, and emission lifetimes of similar to 4 mu s. The electronic structure of these compounds contains ligand-centered LUMO-LUMO+3 levels localized between metal-centered HOMO and LUMO+4 levels.

关键词： compression molding   crystallinity   fiber distribution   glass‐   fiber‐   reinforced polypropylene composite   viscosity  

摘要： The microstructural properties and rheological behavior of the long-glass-fiber-reinforced polypropylene (GF50-PP) composite produced by the compression molding process were studied and modeled. Composite plates of GF50-PP with different thicknesses of 4, 12, and 24 mm have been used to study the effect of glass fiber distribution and various thicknesses on the properties of the core and the surface of the composites. Physicochemical characteristics and rheological behavior of the surface and the core of the plates have been compared. The effect of material sampling area on glass transition temperature, melting temperature, crystallization temperature, degree of crystallinity (X-c), and viscosity were analyzed. Mechanical tests have been carried out to assess the impact of the process parameters on the mechanical characteristics. The results showed that in the compression molding process, three competing parameters should be considered: the X-c, fiber accumulation, and presence of porosity. One can note that this study is applicable to present the relation or interaction between process, microstructure, and properties of the GF50-PP composite prepared by the thermocompression method.

关键词： Dendropanax dentiger   Honey   Physicochemical properties   Chemical composition   Antioxidation  

摘要： Honey produced from medicinal plants has great benefits to human health. Herein, a monofloral honey from Dendropanax dentiger (DDH) was investigated for the first time. The physicochemical properties (moisture, free acidity, pH, hydroxymethylfurfural, diastase activity, electrical conductivity, sugars, and color) of DDH were characterized. The total phenolic and total flavonoids were determined, with contents of 62.89 +/- 10.31 mg GAE/ 100 g and 40.86 +/- 4.32 mg RE/100 g, respectively. A total of 190 compounds were identified and 23 of them were quantified by ultraperformance liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry (UPLC-Q/TOF-MS). Abscisic acid, protocatechuic acid, and 4-hydroxybenzoic acid could be assigned as potential markers of DDH. The antioxidant activity was evaluated in vitro and in vivo, DDH showed potent antioxidant activity. The results showed that DDH was dark-colored, rich in polyphenols, could effectively inhibit lipid peroxidation in the liver of mice, and highlighted the health benefits and commercial value.