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Probiotics have become increasingly recognized for their potential health-promoting properties; however, the viability of probiotics can be affected by storage and transportation processes as well as the stressful environment of the human digestive tract, preventing them from achieving effective concentration (107 CFU/mL). In this regard, the embedding technology of probiotics provides an effective protection method. Dextran-based water in water (W/W) emulsion loaded with Lactobacillus plantarum was used as spinning solution to prepare Lactobacillus plantarum-loaded electrospun fibers. The structure of the W/W emulsion and the electrospun fibers was charactered. Lactobacillus plantarum were uniformly embedded in the internal phase of the W/W emulsion and the loading efficiency was 9.70 ± 0.40 log CFU/g. After 240 min digestion in the gastrointestinal tract, and temperature treatment in 65 °C and 72 °C, the loaded probiotics maintained high activity. Even after 5 days of storage in room temperature and 4 °C, the loaded probiotic activity levels remained high, with counts >8 log CFU/g. These results suggest that probiotics encapsulated by emulsion electrospinning could be potentially delivered in a novel food delivery system used in the future food industry. [ABSTRACT FROM AUTHOR]

Using non-amphiphilic polysaccharide to stabilize oil-in-water emulsions is still a challenge in food industry. Polysaccharide microgels showed emulsifying capacity, however, the stability of the formed emulsions is far from the requirements of the food industry. In this work, agarose microgel/Tween-20 suspensions were prepared and further employed in oil-in-water emulsion stabilization. Focuses were taken on the impact of Tween-20 on the emulsifying properties of agarose microgels. Results suggested that Tween-20 could complex with agarose microgels, and microamounts of Tween-20 (0.02 wt%) could apparently improve the emulsifying performance of microgels. Dynamic interfacial pressure and interfacial adsorption of microgels indicated that appropriate amount of Tween-20 (≤0.04 wt%) could benefit the interfacial adsorption of agarose microgels, while excessive Tween-20 (≥0.08 wt%) could compete with agarose microgels for adsorption sites on oil/water interface. Results of this work supporting that surfactant complexing could be a promising solution to prepare polysaccharides based Mickering emulsions. [ABSTRACT FROM AUTHOR]

To obtain rapeseed protein with low phytic acid (PA), soy protein isolate (SPI) was used to investigate the interactions between SPI and PA. The influence of pretreatment (soaking using salt solution and dialysis) of the defatted rapeseed meal on the PA and protein content in the final rapeseed proteins was also studied. The results showed that electrostatic interactions dominated the protein–PA interaction, which was affected by pH and ionic strength. Accordingly, the pH and ionic strength in the soaking medium also influenced the PA remained in the rapeseed proteins. The PA content decreased with the ionic strength (400–800 mM) and relatively low PA was obtained at pH 6.0 (soaking environment). Finally, 52.8 % of the PA have been removed and PA content remained in rapeseed protein isolate (RPI) reached about 0.84 mg/g, at the same time, the protein content was maintained around 86.70 %. Overall, soaking using salt solution and dialysis could be an effective method to achieve high quality rapeseed protein with low PA. [ABSTRACT FROM AUTHOR]

Erosion seriously threatens the safety of high-speed rotating mechanical components in very harsh service environments, particularly for lightweight titanium alloy matrix material. In order to improve the erosion resistance of titanium alloy, TiAlSiN coatings with different phase compositions are deposited on TC6 titanium alloy using a high-power pulse magnetron sputtering discharge (HPPMS) system under various discharge voltages. The componential and microstructural evolution as well as mechanical properties of the TiAlSiN coatings are evaluated by X-ray diffraction, scanning electron microscopy, and nanoindentation, respectively. The erosion performance relative to titanium alloy is investigated by a sand blasting tester. With the increase in discharge voltage from −500 to −600 V, the peak of discharge current increases from 105 to 225 A. The prepared TiAlSiN coatings show a shift of the preferred crystallographic orientation from (220) to (200), but all of them have a dense nanocomposite structure. Their hardness (H) and elastic modulus (E) gradually increase before decreasing, arriving at maximum values of 35.34 and 360.5 GPa at −570 V. The erosion resistance of the TiAlSiN coatings dependent on the discharge voltage is consistent with the H/E ratio change. The TiAlSiN coatings prepared at −560 V exhibit the optimal erosion resistance, which is 15 times that of the TC6 substrate. The erosion behavior of the coatings is positively correlated with their hardness and toughness. Adjusting the discharge voltage of the HPPMS pulse is finally proved to be an effective way of tailoring the coating phase compositions to improve the erosion resistance of titanium alloy. [ABSTRACT FROM AUTHOR]

As a simple and convenient technology to fabricate micron-to-nanoscale fibers with controllable structure, electrostatic spinning has produced fiber films with many natural advantages, including a large specific surface area and high porosity. Maize zein, as a major storage protein in corn, showed high hydrophobicity and has been successfully applied as a promising carrier for encapsulation and controlled release in the pharmaceutical and food areas. Proteins exhibit different physical and chemical properties at different pH values, and it is worth investigating whether this change in physical and chemical properties affects the properties of electrospun fiber films. We studied the pH effects on zein solution rheology, fiber morphology, and film properties. Rotational rheometers were used to test the rheology of the solutions and establish a correlation between solution concentration and fiber morphology. The critical concentrations calculated by the cross-equation fitting model were 17.6%, 20.1%, 20.1%, 17.1%, and 19.5% (w/v) for pH 4, 5, 6, 7, and 8, respectively. The secondary structure of zein changed with the variation in solution pH. Furthermore, we analyzed the physical properties of the zein films. The contact angles of the fiber membranes prepared with different pH spinning solutions were all above 100, while zein films formed by solvent evaporation showed hydrophilic properties. The results indicated that the rheological properties of zein solutions and the surface properties of the film were affected by the pH value. This study showed that zein solutions can be stabilized to form electrospun fibers at a variety of pH levels and offered new opportunities to further enhance the encapsulation activity of zein films for bioactive materials. [ABSTRACT FROM AUTHOR]

In this research, sodium alginate (ALG) microgels were prepared with different ALG concentrations, and physicochemical and emulsifying profiles of these hydrophilic microgels were comparatively analyzed. Results showed that these microgels possessed different size, hardness, and surface charge. All these microgels could stabilize an oil-in-water emulsion through the Mickering mechanisms, and smaller microgels had better emulsifying capacity. The surface hydrophobicity and interfacial tension of the microgels had no exact effects on their emulsifying behaviors. Compared with the harder microgels (prepared with high ALG concentration, e. g. 4 mg/mL), the emulsifying capacities of the softer ones (prepared with low ALG concentration, e.g. 1 mg/mL) were more sensitive to the high salt concentration (200 mM NaCl) but stable under acidic environment (pH 2.0). Our research would afford a new strategy for the manufacture and application of the novel polysaccharide-based emulsifiers. [ABSTRACT FROM AUTHOR]