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关键词： Trachyte   Characterization   Physicochemical   Electrochemical  

摘要： The trachyte which was the subject of this work was subjected to physicochemical and electrochemical characterizations. X-ray diffraction, Fourier transform infrared (FT-IR), X-ray fluorescence, EDX analysis, scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy were used. The physicochemical characterization have indicated the presence of elements such as Albite (Na (AlSi3O8);Microcline (K(AlSi3O8);Muscovite (KAl2(Si3Al)O-10(OH)(2)) and Diopside Aluminum (Ca(MgFeAl)SiAl)(2)O-6). X-ray fluorescence revealed presence of certain chemical elements in the form of oxide (SiO2: 65.24 wt%;Al2O3: 15.49 wt%;Fe2O3: 5.31 wt%;Ca0: 0.02 wt%;MgO: 0.01 wt%;SO3: 0.03 wt%;Na2O: 3.45 wt%;K2O: 5.65 wt% and P2O5: 0.029 wt%). FTIR and EDX confirmed the results obtained by X-ray and X-ray fluorescence. Presence of quartz, particles of trachyte in the form of clusters of fine aggregates and platelets in the form of rods with irregular contours was confirmed by scanning electron microscopy. Electrochemical characterization showed that our material has affinity with K3Fe(CN)(6)and Ru(NH3)(6)Cl-3, but this affinity is much more pronounced with K3Fe(CN)(6). Modifying glassy carbon electrode with a fine fraction of the trachyte significantly increased sensitivity of the electrode of these species. SiO2/Al(2)O(3)ratio confirmed mechanical resistance of our material and would predestine it in the manufacture of geopolymer binders. Sum% SiO2 + % Al2O3 + % Fe(2)O(3)greater than 70 wt% indicated possibility of using material as pozzolanic materials. High level of alumina, low content of alkaline elements (K2O, Na2O) allow the use of trachyte as a raw material for manufacture of refractory products. This information would allowed us to consider the use of our material for electroanalytical, industrial purposes.

关键词： Argel leaf extract   Antioxidant properties   Rheological properties   Texture profile   Yogurt fortification  

摘要： The fortification of yogurt with natural bioactive compounds could improve its nutritional and health potentials. In this study, physicochemical, antioxidant, and sensory qualities of set-type yogurt were fortified with different concentrations (0.0, 0.1, and 0.2 g/100 mL) of argel leaf extract (ALE) during cold storage was assessed. Both ALE and storage time affected the quality of yogurt at different magnitudes (p < 0.05). ALE increased the acidity, lactic acid bacteria (LAB) count, water-holding capacity (WHC), viscosity, a* and b* values, springiness, total phenolic contents (TPC), antioxidant activity, and sensory attributes of yogurt. However, it reduced the yogurt's pH, syneresis, L* value, hardness, gumminess, adhesiveness, and thiobarbituric acid (TBARS) value. All yogurt types displayed the behavior of weak viscoelastic gels (G' ' G '', tan delta < 1) that had a predominantly solid-like behavior and better stability during storage. During storage, pH, LAB counts, syneresis, viscosity, a* and b*, TPC, antioxidant activity, and sensory attributes were reduced, whereas acidity, WHC, L*, a* and b*, gumminess, cohesiveness, and TBARS values were increased (p < 0.05). It was concluded that ALE (0.1 and 0.2 mg/100 mL) can be used as a natural ingredient to develop a functional yogurt with improved physical, nutritional, antioxidant, and sensorial qualities.

关键词： Andean potato   edible films   gelatin   starch  

摘要： A novel edible film formulation using native Andean potato starch (APS) and gelatin (G) was developed, and evaluated as a function of the APS/G ratio (3:1, 1:1, and 1:3). The films were physicochemically, structurally (FTIR and Raman), morphologically (SEM), thermally (DSC/TGA) and mechanically characterised. The addition of starch increased water resistance, clarity and thermal stability of the films. The SEM micrographs showed a heterogeneous surface and a compact structure. The films also showed low values for both tensile strength and elastic modulus. FTIR analysis revealed intermolecular interactions between the gelatin and starch. Edible film obtained in this work may have potential applications in many fields.

关键词： HMFS   nutritional oil microcapsule   OPO   oxidative stability   SEM  

摘要： To develop nutritional oil similar to Chinese human milk in terms of fatty acids composition and triglyceride, several vegetable oils and 1,3-dioleoyl-2-palmitoylglycerol (OPO) were selected to prepare nutritional oil microcapsule. The result showed that human milk fat substitute (HMFS) prepared by these oils (soybean oil (SO): camellia oil (CMO): high oleic sunflower oil (HOSO): corn oil (CRO): OPO = 28.24:0.00:12.94:8.82:50.00) was the optimal formula. After spray drying, the final microcapsule product was milky white with good solubility and microencapsulation efficiency (MEE = 92.1%). The dispersion coefficient of the microcapsule particle size distribution was 0.200 and the average particle size was 202.767 nm, both particle size distribution experiment and scanning electron microscope (SEM) analysis indicated that the particle size of the microcapsule was uniform and the surface was smooth, After 30 days' accelerated experiment, the peroxide value of microcapsule products was 10.24 meq/kg, indicating the product had good oxidative stability. Practical applications Human milk is considered the most ideal food source for newborns, but not all cases have human milk for infant. Therefore, it is necessary to produce formula milk powder whose composition and function are closer to human milk. This study used five commonly edible oils and added OPO to develop a HMFS similar to human milk in fatty acids and triglycerides. The optimal formula contributed to long shelf life (27 months) and good physicochemical properties, promoting the development of HMFS.

关键词： Loquat polysaccharides   in vitro digestion   Fecal fermentation   Structural characteristic   Gut microbiota  

摘要： The aim of this study was to well understand the dynamic changes of physicochemical properties of polysaccharides from loquat leaves (LLP) during in vitro simulated saliva-gastrointestinal digestion and fecal fermentation and its related impacts on human gut microbiota. Results showed that the contents of reducing sugar of LLP slightly increased during the gastrointestinal digestion, and its molecular weight also slightly decreased, suggesting that LLP could be slightly degraded under the gastrointestinal digestion conditions. Moreover, during the fecal fermentation, the molecular weight of the indigestible LLP (LLP-I) significantly decreased, and the molar ratio of constituent monosaccharides of LLP-I, such as glucuronic acid, galacturonic acid, galactose, and arabinose, significantly changed, indicating that LLP-I could be degraded and consumed by human gut microbiota. Indeed, some beneficial bacteria such as Megasphaera, Megamonas, Bifidobacterium, Phascolarctobacterium, and Desulfovibrio significantly increased, suggesting that LLP-I could change the composition and abundance of gut microbiota. LLP-I could also promote the production of health-promoting short chain fatty acids. Results from this study are benefical to well understand the in vitro digestion and fecal fermentation behaviors of LLP, and LLP can be developed as a potential prebiotic in the functional food industry. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Starch   Thermal processing   Moisture content   Amylose   In vitro digestibility   Crystallinity  

摘要： Moisture and amylose are important factors affecting the quality of heat-treated starches. The amylose content in heat-treated rice starch increased as moisture content (MC) increased from 8% to 30%, but decreased at MC of 70%. With the increase of MC, the paste transmittance, gelatinization temperature, and digestibility of starch increased, whereas the swelling power and enthalpy decreased. The long- and short-range molecular order and the digestive properties of starch with MC <= 30% changed moderately, but high MC (70%) gelatinized the starch and drastically changed the physicochemical properties. High amylose content in rice starch led to low long- and short-range molecular order, swelling power, and gelatinization temperature, but increased resistant starch. The results indicated that 30% of MC separates effects of heat treatment of starch, where low MC (<= 30%) and high amylose lowers digestibility, which is beneficial for diabetics, while high MC (>30%) promotes solubility and transparency. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Green microalga   Chlorella pyrenoidosa polysaccharides   Anti-aging   microRNAs   Intestinal flora  

摘要： A novel polysaccharide from Chlorella pyrenoidosa (CPP) was separated and purified with the average molecular weight 15.8 kDa. It was composed of seven monosaccharides including mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, and arabinose. FT-IR and NMR spectra analysis further revealed that CPP was an acidic polysaccharide consisting of beta-L-Arap-(1 ->,-> 2)-alpha-L-Rhap-(1 ->, beta-D-GlcpA-(1 ->,-> 4)-alpha-D-GalpA(1 ->,-> 6)-beta-D-Glcp-(1 ->,-> 3)-beta-D-Manp-(1 ->, and -> 3, 6)-beta-D-Galp-(1 ->. The CPP treatment could effectively prolong lifespan of Caenorhabditis elegans under the oxidative stress conditions and inhibit the accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA) as well as enhancing the level of superoxide dismutase (SOD). It could up-regulate the expressions of Daf-16 and Skn-1 genes via declining miR-48-3p, miR-48-5p, and miR-51-5p translocation. Moreover, 16S rRNA sequencing revealed that the CPP-enriched Faecalibacterium, Haemophilus, Vibrio, and Shewanella were strongly correlated with SOD, MDA, apoptosis, and ROS. These results indicated that CPP may be considered as a desired ingredient on regulating the aging and oxidative diseases. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Proso millet starch   Proanthocyanidins   Physicochemical   Structure   Starch digestibility  

摘要： The solubility and swelling power, pasting, structure, and digestibility properties of proso millet starch (PMS) with different concentration of proanthocyanidins (PA) were investigated. The results showed that with PA content increasing, the solubility and swelling power of starch increased, the PA accelerated the water absorption and expansion of starch. The results of pasting properties showed that PA increased the peak viscosity of starch, but decreased the setback and pasting temperature. A significant decrease in enthalpy value was measured by differential scanning calorimetry, the enthalpy value decreased from 14.98 J/g to 10.24 J/g at 20% PA concentration. The relative crystallinity of starch, as well as the ratio at 1049/1022 cm(-1), decreased due to the increasing PA concentration, indicating the ordered degree of starch reduced, while the hydrogen bonding in the system was enhanced by PA. The addition of PA decreased the RDS content of uncooked and cooked starch, the RS content increased. When the PA concentration was 20%, the RS content was 1.05 and 1.92 times for native starch, respectively, which significantly reduced the starch digestibility. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Sohphlang   Heat moisture treatment   Annealing   In vitro digestibility   Viscoelastic properties  

摘要： The effect of heat moisture treatment (HMT) and annealing (ANN) on physicochemical and rheological properties and in vitro digestibility of starch extracted from sohphlang (Flemingia vestita) was studied. Modification by HMT and ANN increased amylose content and water absorption capacity. For all modified samples, solubility, swelling power and amylose leaching progressively increased with increasing temperature (50-90 degrees C). Modified starches exhibited higher contents of SDS and RS and lower content of RDS as compared to native starch for both cooked and uncooked samples. The rheological properties of starch pastes were investigated by the power law model. The starch paste samples exhibited shear thinning characteristics and phase angle was closer to 0 degrees. HMT-30 and ANN-80 exhibited greater impact on in vitro digestibility and rheological behaviour among the HMT and ANN starches, respectively. Thus, ANN and HMT could be used for modification of sohphlang starch making them suitable for application in food systems like pasta and noodles. (c) 2020 Elsevier B.V. All rights reserved.

关键词： Amorphous granular potato starch   Hydrothermal treatment   A-type crystalline granular potato starch  

摘要： Using restructuring technology, A- or B-type crystalline granular potato starch was produced from amorphous granular potato starch (AGPS). AGPS was prepared using ethanol-heat processing, and hydrothermal treatments were performed with different moisture contents (18, 29, 200% d.b.) and temperatures (4, 25, 40, 60, 80 degrees C) for 3 weeks. AGPS showed no endothermic peak in a DSC thermogram, while hydrothermally treated AGPS (HAGPS) revealed endothermic peaks. In X-ray diffraction, AGPS displayed an amorphous pattern, and HAGPS displayed A- or B-type crystalline patterns depending on treatment temperature and moisture content. Neither AGPS nor HAGPS had typical RVA pasting curves, and their viscosities gradually increased. Raman spectroscopy and FT-IR confirmed that ordered structure and crystalline regions increased in HAGPS. Resistant starch (RS) and slowly digestible starch (SDS) contents of HAGPS increased but rapidly digestible starch (RDS) content decreased compared to AGPS. These results elucidated that hydrothermal treatment could change the physicochemical properties of AGPS and produce an identical material, such as granular potato starch with A-type and B-type crystalline granular potato starch. (C) 2020 Elsevier B.V. All rights reserved.