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Sensing and monitoring electrical signals and power device parameters within the smart grid network infrastructure plays a fundamental role in assessing the smart devices’ proper functioning. Nevertheless, a key challenge for academic teaching and researching purposes is the elevated cost of real electronic devices, such as current and potential transformers, or even intelligent electronic devices. Therefore, traffic emulators are a valuable solution for the evaluation of new smart grid communication proposals. In this work, we propose TITAN, a tool to support the evaluation of automation systems’ communication networks. TITAN enables the emulation of IEC 61850 communication, ranging from data sensing to data acquisition, thus supporting extensive research and development on this fundamental smart grid domain. This tool can interact and communicate with real elements, such as intelligent electronic devices. It enables the emulation of voltage and current data sensing communication, as well as the implementation of different data acquisition schemes by an emulated supervisory system. Our main contributions are: (i) TITAN, a tool with a distributed microservices architecture to execute communication traffic generation tasks; (ii) a user-friendly interface to integrate and manage all components; and (iii) a proof of concept testbed using TITAN and real teleprotection devices. Real case studies using TITAN reveal its feasibility in supporting low-cost testbeds for research, teaching, and testing purposes in sensing and acquisition for automation systems.

A associação dinâmica de usuários a pontos de acesso e o requisito de cobertura de ampla área tornam desafiador garantir a disponibilidade associada à eficiência energética em redes sem fio de larga escala. Este artigo propõe uma estratégia de provisionamento de pontos de acesso baseada em uma heurística de otimização de múltiplos objetivos. Os objetivos da heurística são maximizar a cobertura, garantindo alta disponibilidade, e minimizar o número de pontos de acesso ativos, melhorando a eficiência energética. A proposta é avaliada através da simulação de uma componente da rede sem fio da Universidade Federal Fluminense com 363 pontos de acesso. A simulação considera fluxos e traços reais de associação de usuários à rede. Os resultados mostram que a estratégia de melhor desempenho é a heurística gulosa que ativa pontos de acesso com o maior número de vizinhos potenciais, porém não ativados. A proposta reduz o número de usuários não servidos e o número de pontos de acesso ativos, assegurando a alta disponibilidade e eficiência energética com uma redução de até 84% no consumo total de energia.

Maillard reaction is a natural occurring reaction that takes place when proteins and saccharides are present. In this study, we have investigated the effect of Maillard reaction on some physicochemical properties of conjugates of whey proteins isolate (WPI) and dextrans (DX) of different molecular weight and their effects on the mechanical and microstructural properties of acid induced gels. The results indicated that the extent of Maillard reaction depended on DX concentration and DX molecular weight (MW). The higher the DX concentration and the lower the DX MW, the higher the extent of Maillard reaction. Conjugates with DX 6 kDa exhibited a decreased from 4.8 up to 4.4 in the isoelectric point, and a decreased in free sulfhydryl groups from 24.37 to 14.81 μmol SH/gprotein. In order to carried out the acid induced gel formation, all the systems were heated at 9% w/w (68.5 °C for 2 h) to form aggregates, which were confirmed by the increase in intrinsic viscosity values in all the systems. The acid gel formation was carried out by using glucono delta-lactone (GDL), which decreased the pH until the isoelectric point of the systems. WPI/DX conjugates of DX 40 kDa formed acid gels in most all DX concentrations, but the conjugation decreased the gel strength and the Young's modulus as compared with WPI gels. Gelation could not be carried out in systems with DX 6 kDa, indicating that Maillard reaction could change or even inhibit the acid gel formation, depending of its extent. After heating, all the systems increased the surface hydrophobicity (H0) as expected, except for WPI/DX6, which showed similar H0 values before and after heating, indicating that this might be the main reason for the inhibition of gel formation.

Cadeias de blocos privadas tendem a aplicar mecanismos de consenso determinísticos como alternativa aos baseados em prova. Mecanismos determinísticos toleram dois tipos de falhas, bizantinas e de parada. O consenso tolerante a falhas bizantinas assume hipóteses restritivas de tempo e número de falhas para garantir a validade, enquanto a terminação depende da difusão de mensagens entre o nós. O consenso tolerante a falhas é menos restritivo para garantir a terminação e maior vazão, sacrificando o acordo. Este artigo propõe um mecanismo de consenso leve baseado na votação por localidade com difusão confirmada de mensagens. Regras de formação nas vizinhanças da rede par-a-par flexibilizam a relação de compromisso entre acordo e o custo de terminação. Resultados experimentais mostram que o acordo e terminação são garantidos no caso de uso de regras mais permissivas, enquanto o custo para alcançar o consenso é reduzido em até 46% em regras mais restritivas com baixo impacto sobre a terminação e o acordo.

Brea gum (BG), which is an exudate from Cercidium praecox tree, was purified and subjected to thermal treatment at 110 °C during different times: 24, 48, 72 and 96 h. Treatment effect was evaluated by analyzing the molecular mass distribution of proteins and polysaccharides, by color and spectrophotometric analyses and by an emulsifying test. BG thermal treated presented changes in the molecular mass of its protein fractions and in its color parameters as a result of non-enzymatic browning reactions. The new molecular species generated were identified by spectrophotometry as Maillard reaction products of the different reaction phases. The modifications in BG structure produced an increase in its surface activity and improved its emulsifying/stabilizing capacity, obtaining corn oil emulsions stable for several months. Finally, the results showed that 24 h of treatment at 110 °C was enough to improve the emulsifying properties of BG. Fil: Castel, María Virginia. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Rubiolo, Amelia Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Carrara, Carlos Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina

This study aimed to evaluate the potential of Brea gum (BG) in the microencapsulation of corn oil in comparison with gum arabic (GA) and evaluate the effect of adding inulin at the matrix formulation. Different concentration of BG and inulin were used to emulsify pure corn oil using a homogenizer followed by an ultrasonic treatment. Then, emulsions were spray dried in laboratory scale equipment to obtain the microcapsules. Overall, powders presented spherical shape with surface concavities, no apparent cracks and high polydispersity. However, some powders containing inulin showed particles that seem to have fused together reflecting a coating effect of inulin. Moisture content of BG powders were low but increased with inulin addition, while water activities (˂0.4) were not affected by inulin. The color analysis showed that BG powders presented lower luminosity and higher red and yellow parameters than GA powder, and adding inulin decreased the lightness, redness and yellowness resulting in powders with more pale color. Encapsulation efficiency increased with BG concentration, reaching 76.12% with 20% of BG. Further efficiency improvement was achieved in presence of inulin, reaching the highest value (91.72) with 20% BG/20% inulin formulation, which was higher than the efficiency achieved with GA (88.66%). It was concluded that the combination of BG and inulin could be used as an alternative wall material for microencapsulation of hydrophobic compounds in replacement of GA. Fil: Castel, María Virginia. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Rubiolo, Amelia Catalina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Carrara, Carlos Roberto. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina

The emulsifying properties of Brea gum (BG), the exudate from Cercidium praecox, were studied in comparison to gum Arabic (GA). Droplet size distributions, rheological properties and stability of corn oil emulsion stabilized with BG and GA solutions were analyzed. The results showed that an increase in BG concentration led to a decrease in Z-average diameter and to an increase in emulsion apparent viscosity and stability. All emulsion flow curves presented shear-thinning behavior at low shear rates and Newtonian plateau at high shear rates. The mechanical spectra showed droplets tending to arrange as a network in the emulsions which was related to the high stability. BG emulsion presented higher viscosity and stability than GA emulsion at the same concentration suggesting that BG could replace GA in some industrial applications. Fil: Castel, María Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Rubiolo, Amelia Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Carrara, Carlos Roberto. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina

Brea gum (BG) is an exudate gum obtained from the Cercidium praecox tree. It is an acidic polysaccharide, made up of 75 g/100 g of hydrolysable sugars, such as L-arabinose, D-xylose, D-glucuronic acid and 4-O-methyl-D-glucuronate. The purpose of this study was to investigate the role of BG as a structural agent in the formulation of emulsion based films. Beeswax (BW) and glycerol (Gly) were added as moisture barrier and plasticizer, respectively. Mechanical and optical properties, microstructure and water vapour permeability were studied. The concentration of BW and Gly was ranged from 0 to 40 g/100 g in a dry basis with respect to BG. We found that, regardless the BW concentration, films with 0 g/100 g Gly were too brittle and they could not be handled. In contrast, films with 40 g/100 g Gly were too tacky and gummy, consequently they could not be unpeeled. Only those films with 20 g/100 g Gly (and 0, 20 and 40 g/100 g of BW) were assayed. Increasing BW concentration resulted in better vapour permeability, to the detriment of its mechanical properties; meanwhile it had no influence in colour parameters. BG may be considered to be a structural support for emulsion based films, being 20 g/100 g of Gly the satisfactory amount of plasticizer.

BACKGROUND Brea gum (BG) is an exudate from the Cercidium praecox tree that grows in semi-arid regions of Argentina. Some previous studies on BG have shown physicochemical characteristics and functional features similar to those of gum arabic. However, there is a need to elucidate the molecular structure of BG to understand the functionality. In this sense, BG was fractionated using hydrophobic interaction chromatography and the obtained fractions were analyzed by size exclusion chromatography. RESULTS Analysis of the fractions showed that the bulk of the gum (approx. 84% of the polysaccharides) was a polysaccharide of 2.79 × 103 kDa. The second major fraction (approx. 16% of the polysaccharides) was a polysaccharide–protein complex with a molecular mass of 1.92 × 105 kDa. A third fraction consisted of protein species with a wide range of molecular weights. The molecular weight distribution of the protein fraction was analyzed by size exclusion chromatography. Comparison of the elution profiles of the exudates in native and reducing conditions revealed that some of the proteins were forming aggregates through disulfide bridges in native conditions. Further analysis of the protein fraction by SDS-PAGE showed proteins with molecular weight ranging from 6.5 to 66 kDa. CONCLUSIONS The findings showed that BG consists of several fractions with heterogeneous chemical composition and polydisperse molecular weight distributions. © 2016 Society of Chemical Industry

Espina Corona Gum (ECG) is extracted from the seeds of Gleditsia amorphoides trees that grow in South-American countries. This gum was approved by the Argentinean food code. It is a galactomannan with an approximate molecular weight of 1.39?106 Da, consisting of 71.4% D-mannose and 28.6% D-galactose with a mannose/galactose (M/G) ratio of 2.5. The mannose forms a linear chain of (1 → 4) β-mannopyranose units with one molecule of D-galactopyranose linked at position 6 every three units of mannose. Structurally, ECG is similar to Guar Gum (GG), which has M/G ratio of 2.0. ECG solutions have a shear-thinning behavior. The viscosity presented good stability during heating, addition of salts and acids. At 1% w/w, ECG exhibits a viscoelastic behavior of weak gel, with light frequency dependence. Moreover, EGC showed very good stabilizing properties in colloid systems by increasing the viscosity of the continuous phase, and thus delaying the creaming and coalescence in emulsions, and the drainage, disproportionation and coalescence in foams.In gels and films, ECG also presented synergistic effects with xanthan gum, and improved the mechanical properties of carrageenans/K+ and whey proteins systems. This gum is a promising hydrocolloid with high potential use in food and pharmauceutical applications. Fil: Spotti, Maria Julia. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Perduca, Martina Juliana. Universidad de la Cuenca del Plata. Facultad de Ingeniería; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Loyeau, Paula Andrea. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Rubiolo, Amelia Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Carrara, Carlos Roberto. Universidad Nacional del Litoral; Argentina

The incorporation of probiotic bacteria to food products is restricted by their instability, so microencapsulation could provide them better protection during storage and gastrointestinal digestion. In this study Bifidobacterium animalis subsp. lactis INL1 was microencapsulated by spray drying using whey proteins isolate (WPI) and dextrans (DX of 6, 70 and 450 kDa) conjugates obtained by Maillard reaction as wall materials. The stability during storage time and temperature, the viability after simulated gastrointestinal digestion and the antioxidant capacity of the microcapsules were assayed. The cell viability was negatively affected by the gastrointestinal digestion and also over the storage time (12 months). Conjugate with DX 6 kDa was the most stable system at 25 °C and showed improved antioxidant capacity whit ABTS[rad]+ technique; meanwhile with [rad]OH technique no differences were found among the samples. Free cells also showed antioxidant activity in all their fractions analyzed using the same techniques. Fil: Loyeau, Paula Andrea. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Spotti, Maria Julia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Vanden Braber, Noelia Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Transferencia de Villa María. Universidad Nacional de Villa María. Centro de Investigaciones y Transferencia de Villa María; Argentina Fil: Rossi, Yanina Estefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Transferencia de Villa María. Universidad Nacional de Villa María. Centro de Investigaciones y Transferencia de Villa María; Argentina Fil: Montenegro, Mariana Angélica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Transferencia de Villa María. Universidad Nacional de Villa María. Centro de Investigaciones y Transferencia de Villa María; Argentina Fil: Vinderola, Celso Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Lactología Industrial. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Lactología Industrial; Argentina Fil: Carrara, Carlos Roberto. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina

In the present work, ovalbumin (OVA) solutions (10 g/L, 50 mM NaCl, pH 7.5) were heat-treated at 75, 80 and 85°C (namely, OVA-75, OVA-80 and OVA-85, respectively), from 0 to 25 min. OVA nanoparticles (OVAn) around 100 nm were obtained. For 3 min of heat treatment, OVAn sizes increased with temperature, but for a heating time longer than 10 min, OVA-75 showed the highest size values. OVAn surface hydrophobicity increased 6-8 folds in comparison with native OVA and wavelength blue shifts of 25-30 nm in maximum fluorescence intensity were registered. These results suggest that buried hydrophobic residues were exposed to the aqueous medium. Binding experiments with linoleic acid (LA) as polyunsatured fatty acid (PUFA) model were carried out. Firstly, binding ability of OVAn was determined from LA titration curves of intrinsic fluorescence measurements. OVA-85 at 5 min presented the highest binding ability and it was used for further binding properties studies (turbidity, particle size distribution -PSD- analysis and ζ-Potential measurements). Turbidity measurement and PSD analysis showed that OVAn-LA nanocomplexes were formed, avoiding LA supramolecular self-assembly formation. The union of LA to OVAn surface confers them significant lower ζ-Potential and larger size. Hence, fluorescence and ζ-Potential results showed that LA would bind to OVAn by mean of hydrophobic interactions. Information derived from this work could be important for potential uses of OVAn for vehiculization of PUFA with applications in several industrial sectors (food, pharmaceutical, cosmetics, etc.). Fil: Sponton, Osvaldo Ernesto. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Perez, Adrián Alejandro. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Carrara, Carlos Roberto. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Santiago, Liliana G.. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina

Edible films with whey protein concentrate (WPC) with a lipid component, sunflower oil (O) or beeswax (W), to enhance barrier to water vapor were obtained. Brea gum was used as emulsifier and also as matrix component. In order to achieve emulsion with small and homogeneous droplet size, an ultrasonicator equipment was used after obtaining a pre-emulsion using a blender. The films were made by casting. Effects of lipid fraction on droplet size, zeta potential, mechanical properties, water vapor permeability (WVP), solubility, and optical properties were determined. The droplet size of emulsions with BG decreased when decreasing the lipid content in the formulation. The zeta potential was negative for all the formulations, since the pH was close to 6 for all of them and pI of BG is close to 2.5, and pI of ß-lactoglobulin and α-lactalbumin (main proteins in WPC) are 5.2 and 4.1, respectively. Increasing W or SO content in blended films reduced the tensile strength and puncture resistance significantly. BG and WPC films without lipid presented better mechanical properties. The presence of lipids decreased the WVP, as expected, and those films having BG improved this property. BG films were slightly amber as a result of the natural color of the gum. BG has shown to be a good polysaccharide for emulsifying the lipid fraction and improving the homogeneity and mechanical properties of the films with WPC and beeswax or oil. Fil: Cecchini, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Spotti, Maria Julia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Piagentini, Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Milt, Viviana Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina Fil: Carrara, Carlos R.. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina

Protein/polysaccharide conjugates have been widely studied because of their good emulsifying properties and their potential use as food ingredients. However, there is little information about the use of these conjugates in gel systems. Rheological properties of conjugates of whey protein isolate (WPI) and dextran (DX) of 15 kDa obtained by Maillard reaction (RM) at different incubation times (2, 5 and 9 days) were studied. Conjugation was confirmed by electrophoresis, conformational changes were studied by DSC and rheological properties were determined by means of an oscillatory rheometer with a temperature ramp ranging from 25 to 90 °C. After each rheological measure, a mechanical spectrum from 0.01 to 10 Hz was also obtained. Electrophoresis indicated the presence of WPI/DX conjugates for all incubation days, though their molecular weight could not be determined. Both, time and temperature of gelation (G′–G″ crossover), increased in WPI/DX conjugate systems compared with WPI without DX (same time of incubation). However, these parameters decreased in WPI/DX mixed system. G′ values at 25 °C decreased in WPI/DX conjugates and increased in WPI/DX mixed system with respect to WPI alone. Frequency sweeps showed that all gels were stable. Fil: Spotti, Maria Julia. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Martinez, María Julia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Pilosof, Ana Maria Renata. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Candioti, Mario César. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Lactología Industrial. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Lactología Industrial; Argentina Fil: Rubiolo, Amelia Catalina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Carrara, Carlos R.. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina

Antioxidant properties of different pilot-plant process streams to obtain Amaranthus mantegazzianus protein concentrates (APC) were evaluated. Conventional process (CP) (alkaline extraction and isoelectric precipitation) and two alternative processes (APs): (1) acid pre-treatment stage combined with isoelectric precipitation and (2) acid pre-treatment stage combined with ultrafiltration were applied at pilot-plant scale to obtain APC. Methanol and water extracts of APC and other fractions obtained in the processes were evaluated by Folin–Ciocalteau method in order to determine total phenolic content and by DPPH radical scavenging activity method to determine antioxidant activity. Acid pre-treatment stage and ultrafiltration caused an effective removal of phenolic compounds yielding on the one hand APC with lower phenolic content than the ones obtained by CP. On the other hand, the acid extract and the whey obtained presented high phenolic content and antioxidant activity and could be used as additives to increased this parameters in food. Finally, evaluated processes could be used to obtain several products (concentrates, whey, extracts) with different phenolic content and antioxidant activity suitable for different applications in food industry. Fil: Castel, María Virginia. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Andrich, Oscar. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Netto, Flávia M.. Universidade Estadual de Campinas. Facultad de Engenharia de Alimentos. Departamento de Tecnología de Alimentos; Brasil Fil: Santiago, Liliana Gabriela. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Carrara, Carlos Roberto. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina

The effect of Maillard reaction on the mechanical properties of whey protein isolate (WPI) heat-induced gels was evaluated. WPI and dextran (15-25 kDa) conjugates were obtained by controlled dry heating during storage at 60°C and 63% relative humidity for 2, 5 and 9 days. Changes in browning intensity and content of free amino groups were used to estimate the Maillard reaction. A decrease in free amino groups of WPI was observed when increasing polysaccharide concentration and reaction time. An increase in both a* and b* CIE Lab colour parameters indicated the development of a reddish-brown colour, typical of the Maillard reaction. Uniaxial compression and stress relaxation tests were performed to measure the mechanical properties of mixed and conjugate gels. Maillard reaction significantly modified the mechanical properties of WPI/DX gels, and even prevented fracture when conjugate gels were subjected to 80% deformation in uniaxial compression test. Fil: Spotti, Maria Julia. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de Los Alimentos; Argentina Fil: Perduca, Martina Juliana. Universidad de la Cuenca del Plata; Argentina Fil: Piagentini, Andrea. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de Los Alimentos; Argentina Fil: Santiago, Liliana. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Rubiolo, Amelia Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Carrara, Carlos. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de Los Alimentos; Argentina

Stoichiometric, kinetic and thermodynamic aspects of complex formation between heat-induced aggregates of ovalbumin (ovalbumin nanoparticles, OVAn) and linoleic acid (LA) were evaluated. Extrinsic fluorescence data were fitted to modified Scatchard model yielding the following results: n: 49 ± 2 LA molecules bound per OVA monomer unit and Ka: 9.80 ± 2.53 × 105 M. Kinetic and thermodynamic properties were analyzed by turbidity measurements at different LA/OVA monomer molar ratios (21.5-172) and temperatures (20-40 °C). An adsorption approach was used and a pseudo-second-order kinetics was found for LA-OVAn complex formation. This adsorption process took place within 1 h. Thermodynamic parameters indicated that LA adsorption on OVAn was a spontaneous, endothermic and entropically-driven process, highlighting the hydrophobic nature of the LA and OVAn interaction. Finally, Atomic Force Microscopy imaging revealed that both OVAn and LA-OVAn complexes have a roughly rounded form with size lower than 100 nm. Fil: Sponton, Osvaldo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Perez, Adrián Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Carrara, Carlos R.. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Santiago, Liliana Gabriela. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina

The aim of this study was to compare protein yield, protein concentration and physicochemical characteristics of Amaranth mantegazzianus protein concentrates (APC) obtained at pilot-scale by a conventional process (CP) (alkaline extraction and isoelectric precipitation) and two alternative processes (AP): (1) acid pre-treatment process combined with isoelectric precipitation and (2) acid pre-treatment process combined with ultrafiltration. Although AP resulted in higher protein concentration, protein yield was lower than in CP. SDS–PAGE and size-exclusion chromatography showed high molecular weight fractions only for isoelectric precipitation concentrates (obtained by CP and AP). The amino acids concentration, especially phenylalanine, isoleucine and methionine, increased in all protein concentrates respect to the amaranth flour. Particularly, the product obtained by ultrafiltration was rich in phenylalanine and lysine, and presented no limiting amino acid with respect to the recommendation of the Food and Agriculture Organization of the United Nations (FAO). In conclusion, process (2) improved protein concentration and nutritional quality (balanced amino acid composition) of A. mantegazzianus protein concentrates respect to CP and process (1), suggesting that the ultrafiltration process is a viable alternative to conventional process and a promising method for obtaining protein concentrates.

Mechanical and microstructural properties of gels composed of whey protein isolate (WPI) and Espina Corona Gum (ECG) were studied. WPI gels were made varying the protein concentration from 12 to 16 g/100 g while mixed gels were obtained at 12 g/100 g protein and varying ECG concentration from 0.12 to 0.60 g/100 g. All gels were obtained by heat treatment (30 min, at 80 °C). Mechanical properties were studied by uniaxial compression and stress relaxation test and gelling properties were discussed in terms of pore size, opacity index, colour parameters and microstructure. Stress (maximum stress) and deformability (Henky’s strain) of mixed gels were seen to increase with the increase in WPI and ECG concentration, thus revealing a higher solid character. This behaviour was consistent with a reduced pore size and increased opacity index of the gel matrix. Microstructure of WPI/ECG mixed gels revealed the existence of a biomacromolecule segregative phenomenon which could promote a greater local protein concentration in separated microdomains.

Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires,ArgentinaThe objective of the present work was to study the effect of bread storage temperature onstarch retrogradation, using water activity measurement and X-ray diffractometry techniqueto analyse the changes produced in the crumb firmness such as recrystallization. Whenstoring bread with crust, the crust tends to trap moisture from the crumb, resulting in adehydration of the crumb with faster staling. For storage temperatures of 25 and 48C, wateractivity decreases as a function of storage time whereas at 188C it is maintained at analmostconstant levelfor23 days.Duringstorage,thestarchmolecules arereassociatedandgenerate a new crystalline order which has a typical XRD pattern: the B-type structure. Thepeakat17.48 isindicativeofthis structureandisrelatedtobreadaging.As observedwiththerecrystallization kinetics, at 188C only crystal growth may occur, whereas at 25 and 48Cthere would be not only growth but also formation of new crystals. At 48C the rate of starchretrogradation is the highest for the studied conditions.

In this work we have studied the interactions between a commercial whey protein concentrate (WPC) and two anionic polysaccharides (sodium alginate, SA, and λ-carrageenan, λ-C) in the aqueous phase. The concentration of WPC at 1.0% and the pH 7.0 of the aqueous phase were maintained constant, while polysaccharides (PS) were evaluated within a 0.0–1.0% concentration range. Interactions between WPC and PS in the aqueous phase were analysed by fluorescence spectroscopy, absorption spectroscopy in the presence of methylene blue (MB), and confocal laser scanning microscopy. The results from these methodologies revealed differences in the molecular dynamics of mixed systems. The nature of the interactions between WPC and PS depended on the PS type, its relative concentration in the aqueous phase and also on the two WPC fractions. Whey protein concentrate/sodium alginate (WPC/SA) mixed systems were distinguished by a tendency to protein aggregation in the aqueous phase and their segregation into separated microdomains. On the other hand, WPC/λ-carrageenan (WPC/λ-C) mixed systems showed a high degree of attractive interactions over the whole range of concentrations. The ultrastructure revealed the existence of hybrid macromolecular entities (biopolymer network). Interaction of WPC and polysaccharide in the aqueous phase has an effect on the adsorption of mixed systems at the air–water interface and on their foaming characteristics. Fil: Perez, Adrián Alejandro. Universidad Nacional del Litoral; Argentina Fil: Carrara, Carlos Roberto. Universidad Nacional del Litoral; Argentina Fil: Carrera Sánchez, Cecilio. Universidad de Sevilla; España Fil: Rodríguez Patino, Juan M.. Universidad de Sevilla; España Fil: Santiago, Liliana Gabriela. Universidad Nacional del Litoral; Argentina

The effect of two non-surface active polysaccharides (sodium alginate, SA, and λ-carrageenan, λ-C) in the aqueous phase on the surface dynamic properties (dynamic surface pressure and surface dilatational properties) of a commercial milk whey protein concentrate (WPC) adsorbed film at the air–water interface has been studied. A whey protein isolate (WPI) was used as reference. The WPC and WPI concentration (at 1.0% wt), temperature (at 20 °C), pH (7), and ionic strength (at 0.05 M) were maintained constant, while the effect of polysaccharide (PS) was evaluated within the concentration range 0.0–1.0% wt. The surface dynamic properties of the adsorbed films were measured in an automatic pendant drop tensiometer. At short adsorption time and in the presence of PS, the rate of diffusion of WPC to the interface was affected by the interactions with PS in the aqueous phase, which could limit protein availability for the adsorption. On the other hand, at long-term adsorption, the magnitudes of the molecular penetration and configurational rearrangement rates of WPC in mixed systems (WPC/PS) reflected the viscoelastic characteristics of the adsorbed films. The attractive interactions between WPC and PS and/or the WPC aggregation in the presence of PS, which depend on the proper polysaccharide and its concentration in the aqueous phase, have an effect on the adsorption kinetic parameters, the amount of WPC adsorbed at the air–water interface, and the dilatational viscoelastic characteristics of WPC/PS mixed systems.

The effects of endosperm hardness and extrusion conditions on expanded product characteristics and flour dispersion viscosity of an extruded maize/soybean (88/12) mixture were studied. Samples were obtained with a Brabender single screw extruder. A factorial experimental design was used to analyze the combined effects on radial expansion of two maize endosperm hardness, extrusion temperature and grits moisture content. Surface response methodology was used to study the effects of extrusion conditions on extrudate properties, taking grits moisture (14–18%) and extrusion temperature (155–185 °C) as factors. Specific mechanical energy consumption, radial expansion, specific volume and product texture were determined on each extrudate sample, and the viscosity of the dispersion from extrudate flour was measured at different solids concentrations. For the 88/12 (maize/soybean) mixture, a softer maize endosperm gives a more expanded product than the harder one. Texture scores were directly related with specific volume. The best extrusion conditions to obtain expanded products and precooked flour from an 88/12 maize/soybean mixture were 170 °C and 14% moisture.

Today amaranth is a promising food source yet its technological properties are not well known. The modification of some properties of an amaranth starch-rich fraction by a controlled heating is studied. This fraction was obtained by the differential milling of Amaranthus cruentus grains. Tests were performed by both fluidized bed and extrusion heating, according to a factorial experimental design of two variables: temperature and moisture, at three levels 150–170–200 °C and 120–160–200 g/kg wb, respectively. Effects were evaluated by the ANOVA method. As responses, solubility and water absorption, amylographic and dynamic rheological properties, crystallinity, granular integrity and resistant starch content were evaluated. Flours obtained from samples heated by fluidized bed gave aqueous dispersions with high consistencies when cooked, and they had low solubility in water and preserved part of the starch crystalline structure. Flours obtained from extrusion-heated samples gave very high solubility in water but had lower consistency of the aqueous dispersions when cooked, and they showed a complete loss of the crystalline and granular structure. By applying each of the two heating processes, it was possible to modify, according to selected targets, the amaranth starch-rich fraction, what would allow to obtain pre-cooked amaranth flours with a wide range of hydration and rheological properties. Fil: Gonzalez, Rolando Jose. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina Fil: Carrara, Carlos R.. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina Fil: Tosi, Enzo Alberto. Universidad Tecnológica Nacional; Argentina Fil: Añon, Maria Cristina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Pilosof, Ana Maria Renata. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Brea gum (BG) is an exudate from the Cercidium praecox tree that grows in semi-arid regions of Argentina. Some previous studies on BG have shown physicochemical characteristics and functional features similar to those of gum arabic. However, there is a need to elucidate the molecular structure of BG to understand the functionality. In this sense, BG was fractionated using hydrophobic interaction chromatography and the obtained fractions were analyzed by size exclusion chromatography.Analysis of the fractions showed that the bulk of the gum (approx. 84% of the polysaccharides) was a polysaccharide of 2.79 × 10(3) kDa. The second major fraction (approx. 16% of the polysaccharides) was a polysaccharide-protein complex with a molecular mass of 1.92 × 10(5) kDa. A third fraction consisted of protein species with a wide range of molecular weights. The molecular weight distribution of the protein fraction was analyzed by size exclusion chromatography. Comparison of the elution profiles of the exudates in native and reducing conditions revealed that some of the proteins were forming aggregates through disulfide bridges in native conditions. Further analysis of the protein fraction by SDS-PAGE showed proteins with molecular weight ranging from 6.5 to 66 kDa.The findings showed that BG consists of several fractions with heterogeneous chemical composition and polydisperse molecular weight distributions. © 2016 Society of Chemical Industry.

In this work, OVA heat-induced aggregates were obtained by controlled heat treatment varying temperature (60, 70 and 80ºC), heating time (3, 5 and10 min), aqueous medium pH (5.5, 6.0 and 6.5) and protein concentration (5, 10 and 14.2 g/L). Particle size distribution and surface characteristics derived from fluorescence spectroscopy (both intrinsic and extrinsic) were determined. Evaluation of these physicochemical properties allowed knowing experimental conditions under which nanometric OVA aggregates (OVAn), with suitable surface hydrophobicity, could be produced. OVAn ability to bind polyunsaturated fatty acid (PUFA) was carried out by turbidity measurement. In these experiments, linoleic acid (LA) was used as a PUFA model. In general, OVA aggregate sizes increased with temperature, time and protein concentration, furthermore at higher pH value, OVA aggregate sizes were lower. OVA aggregates surface hydrophobicity increased with rising heating temperature and the pH value indicating, on one hand, larger protein unfolding and on the other hand lower aggregation via hydrophobic interaction at higher pH value, respectively. However, surface hydrophobicity decreased with concentration suggesting greater aggregation. OVAn obtained at 70°C, 10 g/L, pH 6-6.5 and 70°C, 5 g/L, pH 6 were assayed by LA binding ability. This property was 1.4-2.0 folds greater than for native OVA. Information derived from this work could be of practical interest for the development of innovative PUFAs carrier systems. Fil: Sponton, Osvaldo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Perez, Adrián Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Carrara, Carlos R.. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Santiago, Liliana G.. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina

The effects of heat treatment on the interaction of salt soluble muscle protein and soy protein isolate in model emulsions were studied. Three soy protein isolates (SPI) were used: a commercial one (CSPI) and two pilot plant samples: a native soy protein isolate (NSPI) and an acid treated soy protein isolate (ASPI). Emulsions were prepared with muscle protein (MP), NSPI, ASPI, CSPI and mixtures of MP and the different SPIs, and then treated at 20, 55, 70, 80 and 90°C. Coalescence, soluble protein and electrophoresis of the aqueous phase of the emulsions were evaluated for each temperature. At 20°C the more native soy protein (NSPI) was compatible with MP, producing a stable emulsion that became more stable during heat treatment. CSPI alone could not form a stable interfacial film through the temperature range, however emulsion stabilisation was achieved at 55°C and 70°C when adding MP. Emulsions prepared with MP ASPI were highly unstable at 20°C, while as the emulsion temperature increased, coalescence decreased abruptly and maintained low values at every temperature. MP, NSPI, ASPI and MP NSPI produced stable emulsions both at 20°C and higher temperatures.

The objective of the present work was to analyze molecular and supramolecular changes of bread starch and to relate bread firmness increase during storage with starch recrystallization and water hydration levels and migration in gluten-free bread. At the studied conditions starch was in the supercooled region of the state diagram, at a temperature between Tg (glass transition temperature) and Tm (melting temperature), feasible to crystallize. The crystalline degree during storage was followed by the intensity increase in the X-ray diffraction peaks. During bread storage, water migration occurred from the crumb towards the crust. Water amount and redistribution affected the kind of starch crystallites formed and firmness of aged bread. It was not the total amount of crystalline fraction that determined bread firmness, but the type of crystallites formed. These observations are a further evidence that bread firmness development and starch recrystallization, although being related phenomena, are obviously separate events.

The compatibility of soy proteins with meat protein (MP) in an emulsion system was examined. Three types of soy protein were employed: a commercial soy isolate (CSPI) and two pilot plant samples, an acid treated (ASPI) and a native soy isolate (NSPI). The incorporation of different isolates and the emulsification order affect in a different way the coalescence stability of emulsions prepared with meat proteins. Physicochemical characteristics (surface hydrophobicity, sulfhydryl content, solubility) of the soy proteins cannot explain the different behaviours towards emulsion stability, although the more native sample (NSPI) performed better than the more denature samples (ASPI or CSPI). The addition of NSPI did not modify the high coalescence stability of meat protein emulsion and the effect of the emulsification order was not significant (p 0.05), which suggested compatibility between both proteins. However, the addition of ASPI or CSPI impaired the emulsion stability. When ASPI was emulsified before MP, ASPI inhibited meat protein adsorption and emulsion became highly stable; while when MP was emulsified before or together with ASPI, meat proteins could be displaced from the interfacial film by the ASPI and the emulsion stability was deteriorated. As regards CSPI, all emulsions were highly unstable to coalescence although fractions of both proteins were found in the interfacial film. It could be suggested a mechanism of competitive adsorption when MP is emulsified together with ASPI or CSPI.(

It is well known that protein/polysaccharide conjugates obtained by Maillard reaction (MR) have good emulsifying properties. However, there is little information about the use of these conjugates in gel systems. Structural characteristics and rheological properties of conjugates obtained by MR of whey protein isolate (WPI) and dextrans (DX) of various molecular weight (MW: 6, 40 and 70 kDa) were studied. Conjugation was confirmed by electrophoresis; browning intensity was measured by absorbance at 420 nm; and conformational changes were studied by fluorescence emission of tryptophan (Trp) (λex = 280 nm). Rheological properties were determined by oscillatory rheometry with temperature ramp (25–90 °C). After each measure, a mechanical spectrum (at 25 °C) was obtained. The electrophoresis indicated the presence of WPI/DX conjugates in all systems. Browning intensity increased with decreasing MW of DX. Fluorescence emission of WPI incubated increased, but decreased in WPI/DX incubated systems. The gelation time (obtained by G′–G″ crossover) and G′ value at 25 °C increased in conjugate systems compared with WPI alone. Stability of gel structures were shown by frequency sweeps. Fil: Spotti, Maria Julia. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Martinez, María Julia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Pilosof, Ana Maria Renata. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Candioti, Mario César. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Lactología Industrial. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Lactología Industrial; Argentina Fil: Rubiolo, Amelia Catalina. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Carrara, Carlos Roberto. Universidad Nacional del Litoral. Facultad de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

β-Lactoglobulin (BLG) is a member of lipocalin family, proteins with ability to bind small hydrophobic ligands, such as retinol, vitamins and fatty acids. Moreover, BLG is susceptible to protease action producing a wide range of polypeptides depending on the hydrolysis degree (HD). In the present work, the effect of limited enzymatic hydrolysis on fatty acid binding properties of BLG was studied. Linoleic acid (LA) was used as a model fatty acid. Limited enzymatic hydrolysis was performed using α-chymotrypsin immobilised on agarose microparticles. BLG hydrolysates were produced at HD: 1%, 3% and 5%. In order to determine the influence of HD on BLG molecular weight SDS–PAGE was used. BLG structural modification and LA binding properties were monitored by means of fluorescence spectroscopic techniques. The increase in HD produced: (i) a BLG degradation and a molecular weight distribution of BLG hydrolysates and (ii) an increased exposition of buried hydrophobic residues, however it was observed a decrease in surface hydrophobicity possibly due to a deterioration of hydrophobic protein domains. It was observed that enzymatic hydrolysis treatment produced a decrease in BLG ability for binding LA. It was concluded that limited enzymatic hydrolysis could deteriorate the specific site on BLG structure necessary for binding LA. Fil: Sponton, Osvaldo Ernesto. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Perez, Adrián Alejandro. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Carrara, Carlos Roberto. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Santiago, Liliana Gabriela. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina

Espina Corona Gum (ECG) is extracted from Gleditsia amorphoides seeds and is used as an additive in Argentinean food industry. Its chemical structure corresponds to a galactomannan. ECG was compared with Guar Gum (GG) as regards several properties, among them those related to rheological behavior, the effect of NaCl concentration, temperature and acidity. Experimental results demonstrated that ECG solutions have a shear-thinning behavior, respond to a power-law model, are influenced by temperature, and show a good stability when heated. The presence of NaCl and acidity did not affect ECG solution viscosity. ECG solutions were less viscous and less shear-thinning than GG ones. The viscoelastic behavior shows that, for low frequencies, the viscous modulus is greater than the elastic one up to the crossover point of the frequency, where this behavior is reverted. The apparent viscosity decreased as the frequency of oscillation increased. Fil: Perduca, Martina Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Universidad de la Cuenca del Plata; Argentina Fil: Spotti, Maria Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Santiago, Liliana Gabriela. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Judis, Maria Alicia. Universidad Nacional del Chaco Austral; Argentina Fil: Rubiolo, Amelia Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina Fil: Carrara, Carlos Roberto. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina

Adria´n A. Perez and Carlos R. CarraraInstituto de Tecnologi´a de Alimentos, Facultad de Ingenieri´aQui´mica, Universidad Nacional del Litoral, Santa Fe, ArgentinaCecilio Carrera Sa´nchezDept. de Ingenieri´a Qui´mica, Facultad de Qui´mica, Universidad de Sevilla, Sevilla, Espan˜aLiliana G. SantiagoInstituto de Tecnologi´a de Alimentos, Facultad de Ingenieri´aQui´mica, Universidad Nacional del Litoral, Santa Fe, ArgentinaJuan M. Rodri´guez PatinoDept. de Ingenieri´a Qui´mica, Facultad de Qui´mica, Universidad de Sevilla, Sevilla, Espan˜aDOI 10.1002/aic.12028Published online October 13, 2009 in Wiley InterScience (www.interscience.wiley.com).Protein-polysaccharide (PS) interactions find many applications in food engineeringand new foam formulations. In this article, we have studied the effect of anionic nonsur-face active PSs [sodium alginate (SA) and lambda-carrageenan (k-C)] in aqueous solu-tion on interfacial and foaming characteristics of milk whey proteins [whey protein con-centrate (WPC) and whey protein isolate (WPI)]. Whey protein concentration (1.0% wt),temperature (20 C), pH (7), and ionic strength (0.05 M) of the aqueous media were keptconstant, while PS influence was evaluated within a 0.0–1.0% wt concentration range.The dynamic properties (dynamics of adsorption and surface dilatational properties) ofWPC/PS and WPI/PS adsorbed films were considered in order to correlate the foamingcharacteristics of the biopolymer mixed systems. Foaming characteristics of the biopoly-mer mixed systems depended on the PS relative concentration in the aqueous phase andon the whey protein-PS interactions in solution and at the air–water interface. Dynamicsurface properties of the adsorbed films at short adsorption time had a significant effecton foaming capacity. For a particular system, the overall foam destabilization (foamhalf-life time) and the individual destabilization processes (drainage, disproportionation,and bubble coalescence) depend on the nature of the PS, its relative bulk concentration,and whey protein-PS interactions in the vicinity of the air–water interface. The viscosityof the aqueous phase has an effect on the rate of drainage while the rate of disproportio-nation/collapse is more dependent on the interfacial characteristics of the adsorbed film.

Se realizó una evaluación multicriterio de zonas pesqueras de túnidos mediante el método de función de utilidad (U), considerando tres objetivos de manejo (maximizar las capturas de túnidos, minimizar la mortalidad de delfines y minimizar la captura incidental) y siete ponderaciones entre éstos. Se utilizó como caso de estudio la pesquería de atún con redes de cerco de la flota mexicana en el Pacífico oriental, con datos de 1998 a 2003 del Programa Nacional de Aprovechamiento del Atún y de Protección de Delfines. Las zonas pesqueras se clasificaron de acuerdo a la función de utilidad por trimestre, encontrándose que 64% fueron identificadas como conflictivas (es decir que U0.666 para la ponderación de al menos un tomador de decisiones, pero al mismo tiempo U0.333 para la de al menos otro), por lo que en 2 de cada 3 cuadrantes trimestrales, es necesaria una negociación entre encargados de la toma de decisiones por la naturaleza conflictiva de la pesquería. Se localizaron cuadrantes con características específicas en donde, por ejemplo, algunos lances explicaban los altos valores de captura incidental, o en donde el enfoque de la pesquería hacia el atún aleta azul explicaba la clasificación del cuadrante como excelente. A pesar de que las ponderaciones utilizadas resultaron una buena aproximación, dada la gran variabilidad espaciotemporal de los recursos pelágicos, las preferencias (ponderaciones) reales deberían estar diferenciadas en espacio y tiempo para ser realmente útiles en el proceso de toma de decisiones. Un aspecto importante es que ya se han implementado estrategias y planes de manejo bien estructurados y eficientes para alcanzar dos de los objetivos de manejo (maximizar las capturas de túnidos y minimizar la mortalidad de delfines), mientras que para el tercero (minimizar la captura incidental) hasta el momento no se cuenta con un esquema parecido.

Transdermal gels are designed to deliver sustained drug amounts, resulting in systemically consistent levels. They represent an improvement compared with transdermal delivery by patches because they offer more dosage flexibility, less irritation potential and a better cosmetic appearance. Advanced Transdermal Delivery (ATD) gel technology was developed in order to provide enhanced passive skin permeation of various active drugs for the treatment of many conditions, including hypogonadism, female sexual dysfunction, postmenopausal symptoms, overactive bladder and anxiety. The technology consists of a combination of solvent systems and permeation enhancers enabling systemic drug delivery, and is covered by many patents. Pharmaceutical development of formulations based on the technology allowed optimisation of physicochemical parameters (rheological profile, pH) as well as skin permeation properties (type and concentration of permeation enhancers, thermodynamic activity of the drug). This gel technology has demonstrated to be efficient for many drugs, as shown in the preclinical and clinical pharmacokinetic studies presented in this technology evaluation.

The behaviour of fixed-bed reactors, which have an immobilised enzyme on the packing surface, was studied considering steady-state conditions and external mass transfer resistance in the fluid around catalyst spherical particles. Solutions were obtained by integration of the plug-flow model equation and by the orthogonal collocation method of the second order differential equation of the axial dispersion flow model. Both models were analysed for lactose hydrolysis with β-galactosidase immobilised on chitosan using different kinetic reaction mechanisms after determining the specific parameters. The calculated results show the importance of the hydrodynamic and kinetic reaction parameters for error reduction in the prediction of the experimental behaviour. Fil: Carrara, Carlos Roberto. Universidad Nacional del Litoral; Argentina Fil: Mammarella, Enrique José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina Fil: Rubiolo, Amelia Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentina