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991.
Lucía Fernández-Espada Carlos Bengoechea José Alberto Sandía Felipe Cordobés Antonio Guerrero 《应用聚合物科学杂志》2019,136(5):47012
The addition of salts, like sodium bicarbonate (SB) or carbonate (SC), into the formulation of bioplastic materials may alter their hydrophilic character to a significant extent. Soy protein isolate (SPI) is a byproduct of the soybean oil industry, which, when properly blended with glycerol (GL), can be further processed through a lab-scale injection molding device. A maximum in the water uptake around 2250 or 2500% is obtained for bioplastics obtained when either SB or SC content is around 1 wt %, respectively. Thus, they exceed the limit to be considered superabsorbent materials (SAMs). Regarding their mechanical properties, a higher presence of SB within the SPI/GL matrix provides materials with a higher extensibility and lower Young's modulus. A higher water uptake is observed after replacing SB for SC in the formulation, probably related to a higher alkalinization of the material as well as to the high hydrophilicity of the carbonate. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47012. 相似文献
992.
Jeferson L. da Silva Raul C. Maranhão Michelle S.M. Silva Rodrigo G. Dias Fatima R. Freitas Wladimir Bolani José R. Lemos Junior Cleber R. Alves Patrícia A. Oliveira Guilherme B. Alves Edilamar M. Oliveira Carlos Eduardo Negrao José Eduardo Krieger Alexandre C. Pereira Gisele A. Silva José P. Souza Carmen G.C. Vinagre 《Lipids》2019,54(6-7):381-388
Exercise training not only improves the plasma lipid profile but also reduces risk of developing coronary heart disease. We investigate whether plasma lipids and high density lipoprotein (HDL) metabolism are affected by aerobic training and whether the high-density lipoprotein cholesterol (HDL-C) levels at baseline influence exercise-induced changes in HDL. Seventy-one male sedentary volunteers were evaluated and allocated in two subgroups, according to the HLD-C levels (< or >40 mg/dL). Participants underwent an 18-week aerobic training period. Blood was sampled before and after training for biochemical analysis. Plasma lipids, apolipoproteins, HDL diameter, and VO2 peak were determined. Lipid transfers to HDL were determined in vitro by incubating plasma samples with a donor lipid artificial nanoemulsion. After the 18-week period of aerobic training, the VO2 peak increased, while the mean body mass index (BMI) decreased. HDL-C concentration was higher after the training period, but low-density lipoprotein cholesterol (LDL-C) and non-HDL-C did not change. The transfer of esterified cholesterol and phospholipids was greater after exercise training, but the triacylglycerol and unesterified cholesterol transfers were unchanged. The HDL particle diameter increased after aerobic training in all participants. When the participants were separated in low-HDL and normal-HDL groups, the postaerobic exercise increment in HDL-C was higher in the low-HDL group, while the transfer of esterified cholesterol was lower. In conclusion, aerobic exercise training increases the lipid transfers to HDL, as measured by an in vitro method, which possibly contributes to the classical elevation of the HDL-C associated with training. 相似文献
993.
Rodrigo Battisti Eduardo Hafemann Carlos Alberto Claumann Ricardo Antonio Francisco Machado Cintia Marangoni 《Polymer Engineering and Science》2019,59(5):891-898
This study provides a novel value‐added utilization of the agroindustrial waste of royal palm tree leaf sheath to produce cellulose acetate. One of the motivations of this work was the fact that Brazil is one of the largest heart of palm producers in the world. However, as a result of extraction and processing, tons of waste are generated and discharged to the environment. Such waste is rich in lignocellulosic material, which could be reused to obtain derivatives of interest and commercial value. The synthesis of cellulose acetate was performed through a homogeneous acetylation reaction. Three different conditions were tested for delignification of the raw material, which resulted in a reduction in lignin content from 17.75 to 7.72%. The highest yield of cellulose acetate reached 99.5%, with degree of substitutions ranging between 2.08 and 2.82, which indicates satisfactory conversion. The Fourier transform infrared spectrum showed that practically all hydroxyl groups were replaced by acetate groups; this was also confirmed by nuclear magnetic resonance analysis. X‐ray diffraction analysis showed that the cellulose acetate crystallinity index was 8.9%. This demonstrates the viable potential of cellulose acetate production with low cost and use of highly available agroindustrial waste. POLYM. ENG. SCI., 59:891–898, 2019. © 2018 Society of Plastics Engineers 相似文献
994.
Katarzyna Skryplonek Marta Henriques David Gomes Jorge Viegas Catarina Fonseca Carlos Pereira Izabela Dmytrów Anna Mituniewicz-Małek 《Journal of dairy science》2019,102(9):7838-7848
Frozen yogurt is a type of dairy product that is considered to be a more healthful alternative to conventional ice cream due to its lower fat content and the presence of viable lactic acid bacteria. Lactose-free products are a growing trend in the dairy industry, and lactose-free yogurts and ice creams can both be found on the market. However, lactose-free frozen yogurt has not yet reached the market. In this study, we aimed to investigate the effect of adding κ-carrageenan (0.05, 0.1, and 0.15%) and corn starch (1, 2, and 3%) on acidity, texture, viscosity, overrun, melting properties, color attributes, and sensory characteristics of lactose-free frozen yogurts. Lactose was reduced by enzymatic hydrolysis during the fermentation process. The effectiveness of the hydrolysis was measured by HPLC, and lactose was reduced to 0.05% after 80 min of incubation with the enzyme. The addition of stabilizers did not change overrun and melting properties of frozen yogurt, but it did affect pH, titratable acidity, and color parameters. The product with 0.15% κ-carrageenan had the highest hardness and stickiness values. Moreover, κ-carrageenan had a positive effect on sensory attractiveness of lactose-free frozen yogurt, and it reduced the coarse texture in comparison with the control without stabilizers. A lactose-free frozen yogurt with good quality and nutritional characteristics was produced, particularly with the use of κ-carrageenan as stabilizer. 相似文献
995.
996.
Jos Agustín Tapia‐Hernndez Carmen Lizette Del‐Toro‐Snchez Francisco Javier Cinco‐Moroyoqui Saúl Ruiz‐Cruz Josu Jurez Daniela Denisse Castro‐Enríquez Carlos Gregorio Barreras‐Urbina Guadalupe Amanda Lpez‐Ahumada Francisco Rodríguez‐Flix 《Journal of food science》2019,84(4):818-831
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
997.
998.
Francisco Rodríguez‐Flix Carmen Lizette Del‐Toro‐Snchez Francisco Javier Cinco‐Moroyoqui Josu Jurez Saúl Ruiz‐Cruz Guadalupe Amanda Lpez‐Ahumada Elizabeth Carvajal‐Millan Daniela Denisse Castro‐Enríquez Carlos Gregorio Barreras‐Urbina Jos Agustín Tapia‐Hernndez 《Journal of food science》2019,84(10):2883-2897
999.
Production of antioxidants by non-isothermal autohydrolysis of lignocellulosic wastes 总被引:1,自引:0,他引:1
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
1000.
Relationship between collagen characteristics,lipid content and raw and cooked texture of meat from young bulls of fifteen European breeds 总被引:1,自引:0,他引:1
Mette Christensen Per Ertbjerg Sebastiana Failla Carlos Sañudo R. Ian Richardson Geoff R. Nute José L. Olleta Begoña Panea Pere Albertí Manuel Juárez Jean-François Hocquette John L. Williams 《Meat science》2011
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