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991.
Currently, electrospraying is a novel process for obtaining the nanoparticles from biopolymers. Zein nanoparticles have been obtained by this method and used to protect both hydrophilic and hydrophobic antioxidant molecules from environmental factors. The objective of this work was to prepare and characterize gallic acid‐loaded zein nanoparticles obtained by the electrospraying process to provide protection to gallic acid from environmental factors. Thus, it was related to the concentration of gallic acid in physicochemical and rheological properties of the electrosprayed solution, and also to equipment parameters, such as voltage, flow rate, and distance of the collector in morphology, and particle size. The physicochemical properties showed a relationship in the formation of a Taylor cone, in which at a low concentration of gallic acid (1% w/v), low viscosity (0.00464 ± 0.00001 Pa·s), and density (0.886 ± 0.00002 g/cm3), as well as high electrical conductivity (369 ± 4.3 µs/cm), forms a stable cone‐jet mode. The rheological properties and the Power Law model of the gallic acid‐zein electrosprayed solution demonstrated Newtonian behavior (n = 1). The morphology and size of the particle were dependent on the concentration of gallic acid. Electrosprayed parameters with high voltage (15 kV), low flow rate (0.1 mL/hr), and short distance (10 cm) exhibited a smaller diameter and spherical morphology. FT–IR showed interaction in the gallic acid‐loaded zein nanoparticle by hydrogen bonds. Therefore, the electrospraying process is a feasible technique for obtaining gallic acid‐loaded zein nanoparticles and providing potential protection to gallic acid from environmental factors.  相似文献   
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Selected lignocellulosic wastes were subjected to autohydrolysis processing (in media containing hot, compressed water) at temperatures in the range 200-240 °C. The aqueous phases from treatments were extracted with ethyl acetate and the soluble solids were redissolved in 80% ethanol (to obtain a more hydrophylic product). The resulting extracts were assayed for yield, phenolic composition and antioxidant capacity. The highest percentages of solid solubilization upon autohydrolysis (31 and 29%) were observed for corncob and almond shells, respectively. Ethanol redissolution of ethyl acetate extracts from almond shells, chestnuts burs, and grape pomace resulted in concentrates with decreased phenolic contents and lower antioxidant capacities (measured by the DPPH scavenging radical method). The best concentrate contained benzoic and cinnamic acids as major phenolic components.  相似文献   
995.
This paper reports a FT-IR study for probing lipid and protein structural changes and their interactions in various oil-in-water emulsions. Two different emulsions were prepared using sodium caseinate, as stabilizer system, without and with microbial transglutaminase (MTG), denominated E/SC and E/SC + MTG respectively. Proximate composition, fat and water binding properties and textural characteristics were also evaluated in the emulsions. Penetration force and gel strength values were used to distinguish different (P < 0.05) textural behaviours depending on the formulation of emulsifying system. E/SC + MTG emulsion showed gel textural behaviour while E/SC lack of this property. The spectral results showed frequency upshifting of the amide I band in going from protein stabilizer systems isolate (the solution used as reference) to their corresponding emulsions, what is attributable to greater protein structural order upon emulsion formation. Enzymatic action of MTG in the sodium caseinate stabilizing system induces structural changes, in terms of lipid chain disorder or lipid–protein interactions and protein secondary modifications, which may reflect the formation of a gel structure in the emulsion. These results could help to choose the stabilizing system that is most suitable and effective for its use in the formulation of food products.  相似文献   
996.
Variations in texture were determined for 10 day aged raw and cooked Longissimus thoracis (LT) muscle from 436 bulls of 15 European cattle breeds slaughtered at an age of 13–16 months. Variations in texture were related to differences in pH 24 h post-mortem, sarcomere length, collagen characteristics and lipid content. The shear force of cooked meat samples varied from 43.8 to 67.4 N/cm2. Simmental, Highland and Marchigiana cattle had the highest shear force values and Avileña-Negra Ibérica, Charolais, Casina and Pirenaica cattle had the lowest values. Cooked meat toughness showed a weak negative correlation to lipid content (P < 0.001) but no correlation to collagen characteristics. Raw meat texture measured by compression correlated positively (P < 0.001) with total and insoluble collagen. In conclusion, collagen characteristics showed correlation to raw meat texture but not to cooked meat toughness of LT muscle in European young bulls.  相似文献   
997.
A duplex real-time PCR assay based on TaqMan probe technology was developed for the authentication of two commercially important anglerfish species (Lophius budegassa and L. piscatorius). This technique uses the cytochrome oxidase subunit I and allows the unambiguous identification of this species. It is notable for its simplicity, rapidity, highest potential for automation and minor risk of contamination. The TaqMan real-time PCR is currently the most suitable method for screening, allowing the detection of fraudulent or unintentional mislabeling of these species. The method can be applied to all kind of products as fresh, frozen, and precooked products. The developed methodology, which uses two specific primer–probe sets, has been validated and subsequently applied to 40 commercial samples labeled as any anglerfish species in order to determinate whether the species used for their manufacturing correspond to these species. The methodology herein developed is appropriate to clarify questions related with the correct labeling of commercial products, traceability in commercial trade, and fisheries control.  相似文献   
998.
Pattern Analysis and Applications - As is widely acknowledged, the transportation of goods by road can, in one way or another, be linked to a range of macroeconomic indicators. A hybrid artificial...  相似文献   
999.
This paper presents a methodology for the earthquake design of reinforced concrete (RC) bridge infrastructures based on the application of multi-objective  相似文献   
1000.
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