PDF superior Impact of yeast and fungi (1 3)(1 6) β glucan concentrates on viscoelastic behavior and bread making performance of gluten free rice based doughs

Impact of yeast and fungi (1 3)(1 6)  β glucan concentrates on viscoelastic behavior and bread making performance of gluten free rice based doughs

Impact of yeast and fungi (1 3)(1 6) β glucan concentrates on viscoelastic behavior and bread making performance of gluten free rice based doughs

of 1,6 β-linked branches. In contrast, oat and barley cell walls contain unbranched β-glucans with 1,3 and 1,4 β-linked glycopyranosyl residues. BG from cereals is classified as dietary fiber that is not hydrolyzed in the human digestive tract, and is a non-calorific ingredient (Borchani et al., 2016). BG obtained from yeast and mushrooms presents positive effects on human health, such as immune-stimulation, anti-inflammatory, antimicrobial, and anti-tumoral responses (Chan et al., 2009; Kim et al., 2011; Rop et al., 2009; Santipanichwong & Suphantharika, 2009; Worrasinchai et al., 2006). (1→3)(1→6)-β-glucans have also demonstrated hypoglycemic activity in animal studies, and are likewise known for their hypocholesterolemic activity and in reducing atherosclerosis (Miranda-Nantes et al. 2011). Certain preparations of yeast-derived (1→3)(1→6)-β-glucan have recently been approved as novel food ingredients by the European Food Safety Authority (EFSA) and given “Generally Recognized as Safe” status by US Food and Drug Administration. So far, the EFSA has not yet approved a health claim on immune function for yeast (1→3)(1→6)-β-glucan preparations (EFSA, 2011; Samuelsen et al., 2014). The cell wall of yeast (Saccharomyces cerevisiae) contains about 50-65% of (1→3)(1→6)-β- glucan (Kogan & Kocher, 2007). The difference in molecular and structural features according to the origin of BG leads to differences in their physical properties and, thereby, different effects on the functionality of food systems (Banchathanakij & Suphantharika, 2009). The potential applications of (1 → 3)(1 → 6)-β-glucan in food stuffs have previously been reported. This includes as a thickening, water-holding, and oil-binding agent and emulsion stabilizer, as a fat replacer in food emulsions (Santipanichwong & Suphantharika, 2009; Worrasinchai et al., 2006), and as a texture modifier in starch gels . (Satrapai & Suphantharika, 2007). However, its
Mostrar más

21 Lee mas

Mejora nutricional y funcional de panes sin gluten: adición de beta glucanos de diferentes orígenes y pesos moleculares atendiendo a las declaraciones de salud aprobadas por la EFSA

Mejora nutricional y funcional de panes sin gluten: adición de beta glucanos de diferentes orígenes y pesos moleculares atendiendo a las declaraciones de salud aprobadas por la EFSA

protocols such as drying /trituration and washing, instead of β-glucan concentrates were used. Regarding gluten-free products, few studies have explored the use of these polysaccharides on the fortification of gluten-free cakes (Kim et al., 2011), rice noodles (Heo et al., 2014) and bread (Kittisuban et al., 2014). Kim et al. (2011) used β-glucan extracts from Lentinus edodes (insoluble fiber) as a high-fiber and low- calorie ingredient in wheat flour cakes and found an increase in batter viscosity with more pronounced shear-thinning behavior and enhanced elastic properties. Although no significant differences were observed between the control and cakes containing 1 g of yeast β-glucan per serving, a further increase of polysaccharide level resulted in decrease of the volume and increase of the hardness of cakes. Heo et al. (2014) obtained rice noodles with greater extensibility and firmness with Lentinus edodes fortification for all concentrations tested (4, 8 and 12%). Kittisuban et al. (2014) used response surface methodology to analyze effects of hydroxypropylmethylcellulose (HPMC), yeast β-glucan (insoluble), and whey protein isolate (WPI) on physical properties of gluten-free rice breads and found a decrease in bread volume and a increase in crumb hardness with increasing β-glucan concentration (from 1 g / 100 g to 2 g / 100 g). However, in this work the optimum level of added water to the dough was not investigated, which is considered one of the most important factors for optimization of the quality of the bread fortified with any fiber. In addition, fungi and yeast β-glucans exhibit differences in solubility, which may lead to different behavior in complex food matrices (Martinez et al., 2014); this fact has also to be considered in food fortification with microbial β-glucans. In general, incorporation of soluble fibers into bread formulations, such as inulin or polydextrose decrease the dough consistency, and favour a better bread development, darker breads, lower crumb hardness and higher cell density compared to control breads. In contrast, insoluble fibers from oat, bamboo, potato and pea, particularly those with coarse particle size, decreased the bread specific volume and increased largely the crumb firmness (Martinez et al., 2014).
Mostrar más

286 Lee mas

Effect of Microwave Radiation Pretreatment of Rice Flour on Gluten Free Breadmaking and Molecular Size of β Glucans in the Fortified Breads

Effect of Microwave Radiation Pretreatment of Rice Flour on Gluten Free Breadmaking and Molecular Size of β Glucans in the Fortified Breads

fraction of the HMW-BG sample were eluted in the void volume of the size exclusion columns, i.e. the β-glucan added to the gluten-free doughs had a Mp > 9 x 10 5 Da. However, for the β-glucans isolated from the control bread made from the untreated rice flour there was a large reduction in Mp, as the main eluting peak was ~ 0.23 x 10 5 Da, presumably due to polysaccharide degradation by endogenous β-glucanases of the rice flour during the breadmaking process (Table 1). Similarly, several researchers have previously noted a considerable reduction of β-glucan molecular weight during production of yeast-leavened bakery products from oat bran as well as rye and barley flour which was attributed to endogenous β-glucanase activity (Aman et al. 2004; Andersson et al. 2004; 2008; 2009; Lazaridou et al. 2014; Trogh et al. 2004); apparently, the molecular weight of β-glucans in the final products decreases with increasing mixing and dough fermentation time. Recently, an endogenous β-glucanase activity was also found in rice flour (Perez-Quirce et al. 2016) which can cause severe reduction of oat and barley β-glucans during breadmaking when these polysaccharides are added as concentrates to rice-based gluten-free bread formulations (Ronda et al. 2015).
Mostrar más

25 Lee mas

Rice flour physically modified by microwave radiation improves viscoelastic behavior of doughs and its bread-making performance

Rice flour physically modified by microwave radiation improves viscoelastic behavior of doughs and its bread-making performance

Thermal treatments deliver the possibility to impact both nutritional and functional properties during processing, as changing moisture and thermal conditions create an environment for different micro and macroscopic changes of complex matrix of flour (BeMiller and Huber, 2015). However, typical heat application results in high potential costs of industrial scaling up. Meanwhile, application of microwaves (MW) as heat providing media seems to be reasonable from both cost and functionality effectiveness change perspectives (Wu et al., 2008; Xu et al., 2013). Our previous studies investigated the application of microwave energy to rice flour for -glucanase inactivation and enhancement of -glucans bioactivity of fortified rice-based gluten-free breads (Pérez- Quirce et al., 2017) while bread physical quality was hardly affected by flour MW pretreatment. In fact, only a slightly higher loaf specific volume was noted for breads made from the most intensively treated flour (4 min of MW treatment at 25% moisture content and 96ºC maximum temperature reached by flour). No significant change was observed in the pasting properties of the treated flours.
Mostrar más

24 Lee mas

Decay And Termite Resistance Of Particleboard Manufactured From Wood, Bamboo And Rice Husk

Decay And Termite Resistance Of Particleboard Manufactured From Wood, Bamboo And Rice Husk

A Nasutitermes corniger Motsch. full colony (with all castes including king and queen) was placed inside a fibrocement box, disposed in a grid over the layer of humid sand and the metal tray with the samples. Afterwards, the fibrocement box was covered using a nylon screen in order to impede termite escape. The samples were exposed to termites for 45 days, in a climate-controlled room (28°C and 75% relative moisture). After the assay, the samples were again conditioned until the weights had stabilized (20°C and 65% relative moisture) and weighed in order to evaluate the percentage of mass loss.
Mostrar más

8 Lee mas

Inactivation of Endogenous Rice Flour β Glucanase by Microwave Radiation and Impact on Physico chemical Properties of the Treated Flour

Inactivation of Endogenous Rice Flour β Glucanase by Microwave Radiation and Impact on Physico chemical Properties of the Treated Flour

The (1-3) (1-4) β-D-glucans (BG) are major components of cell walls in the starchy endosperm and the aleurone layer of commercially important cereals, mostly oat and barley and to a lesser extent rye and wheat (Lazaridou and Biliaderis 2007). These polysaccharides are classified as soluble dietary fibre with well recognized nutrtitional implications as specified in several health claims authorized by many regulatory authorities around the globe. The US Food and Drug Administration (USFDA) (2005) has approved a health claim for the reduction of coronary heart disease risk with a daily consumption of 3g of β-glucan soluble fiber from whole grain barley or oat and dry milled barley/oat grain products as part of a low saturated fat and low cholesterol diet. Recently, the European Food Safety Authority (EFSA) has also authorized a health claim, according to which barley β-glucan ingestion leads to the reduction of blood plasma cholesterol levels, which is a major risk factor for the development of coronary heart disease (EFSA 2011a); the recommended daily intake is 3g of oat β-glucan as part of a balanced diet. Other health claims for oat and barley β-glucans were also approved by EFSA concerning the reduction in post-prandial glycemic responses, at doses of about 4g of β-glucans per 30g of available carbohydrates in bread and pasta products (EFSA 2011b), and the increase of faecal bulk (EFSA 2011c); the latter claim can be used for foods containing barley or oat grain fiber at least 6g/100g product or 3g/100 kcal.
Mostrar más

27 Lee mas

WORLD DEVELOPMENT REPORT 2015: MID, SOCIETY AND BEHAVIOR

WORLD DEVELOPMENT REPORT 2015: MID, SOCIETY AND BEHAVIOR

Another example of effective framing is choice simplification, particularly with respect to the number of alternatives presented. For most products, an agent, adviser, or bank can present the decision maker with only a limited set of alternatives. If people had unlim- ited bandwidth, more information would always be better for decision makers, assuming that they could freely choose the number of alternatives they want to consider, given some search cost. In practice, however, people are often overwhelmed by a large number of alternatives and end up postponing decisions or using simple heuristics or rules of thumb (Johnson and oth- ers 2012; Drexler, Fischer, and Schoar 2014). Reducing the number of alternatives can therefore be an effec- tive intervention. It has been shown that procrastina- tion is less severe as the choice set becomes smaller (Tversky and Shafir 1992). A study of consumer credit in South Africa finds that more loans were made when a smaller number of combinations of interest rates and loan amounts were suggested to customers (Bertrand and others 2010). The effect of this simple framing manipulation was equivalent to a 2.3 percent reduc- tion in the loan interest rate. Similarly, in their current work, Giné, Martinez Cuellar, and Mazer (in progress) are finding a significant improvement in the ability of respondents in Mexico to identify the optimal loan and savings products when they were presented with succinct summary information about savings rates and loan costs, as compared to a finer breakdown of commissions, fees, and returns.
Mostrar más

236 Lee mas

Employees' proactive behavior and innovation performance  Examining the moderating role of informal and formal controls

Employees' proactive behavior and innovation performance Examining the moderating role of informal and formal controls

way to highlight individual strengths and improve performance (e.g., Crant, 2000). Previous studies point out the benefits of proactive behaviors for individuals, such as supporting creativity and improving task performance (e.g., Seibert et al., 2001; Hermann and Felfe, 2014), and also for firms’ innovation success (e.g., Kickul and Gundry, 2002). Proactive behavior has been mainly analyzed as an individual construct. Some studies, however, suggest the interest of analyzing collective constructs due to their close connection with organizational performance (e.g., Baer and Frese, 2003; Pugh and Dietz, 2008). Hence, we examine collective proactive behaviors displayed by the group of employees from the R&D area. Based on previous studies of proactivity as a collective phenomenon (e.g., Williams et al., 2010; Erkutlu and Chafra, 2012), we define collective proactive behavior as the behavior of employees from the R&D area who, as a group, are able to take initiatives to anticipate and create changes. Several scholars (e.g., Morgeson and Hofmann, 1999; Whitman et al., 2010; Williams et al., 2010; Dawkins et al., 2015) have explained that collective constructs represent the mode of behavior in the area as a whole, the ability to behave collectively derived from the combination of ideas and interactions between the members of the area (i.e. they engage in common processes and events, and share knowledge). These previous contributions suggest that in some way collective proactive behavior gathers the collective mind (Weick and Roberts, 1993) in the R&D area; in other words, there is a behavioral pattern to undertake actions proactively, which may differ in structure from average individual proactive behavior due to the interactions between the members of the area.
Mostrar más

34 Lee mas

16638323

16638323

As mentioned above, two methods are found in the scientific literature to solve the described set of equations. The analogy to heat transfer alone [3] is based on the definition of new dependent variables, called character- istic potentials, and some assumptions. The characteristic potentials and assumptions are chosen so that the original equations for mass and enthalpy are divided in two sets of equations that are analogous to the heat regenerator equations. Then the results given in the scientific litera- ture for heat regenerators can be used to obtain a solution for the heat and mass regenerator. It is an approximate method because of the assumptions made. On the other hand, finite difference methods solve numerically the problem, getting accurate results [1]. A brief description of the finite difference method is outlined next. On a first step, governing equations are transformed in dimension- less ones:
Mostrar más

8 Lee mas

Performance, carcass and ruminal fermentation characteristics of heifers fed concentrates differing in energy level and cereal type (corn vs. wheat)

Performance, carcass and ruminal fermentation characteristics of heifers fed concentrates differing in energy level and cereal type (corn vs. wheat)

A total of 144 beef heifers (218 ± 26.4 kg body weight) were housed in 24 pens (6 animals each) and used in a 168-day feedlot study to evaluate the influence of cereal type and energy level on performance, carcass quality and ruminal fermentation. Four concentrates were formulated according to a 2×2 factorial arrangement of treatments, with two energy levels (1,452 vs. 1,700 kcal net energy/kg) and two main cereals (wheat vs. corn). Concentrate and straw were offered ad libitum. Concentrate intake and body weight were recorded on days 42, 84, 126 and 168. Ruminal fluid was obtained by ruminocentesis from 3 heifers per pen on days 1, 84 and 168; and carcass weight, classification and yield, were determined in the same animals. Heifers fed high-energy diets had lower intake (6.97 vs. 7.29 kg fresh matter/d; p=0.011), and lower concentrate to gain ratio (5.15 vs. 5.66 kg/kg; p=0.002) than those fed low energy concentrates, and tended (p=0.069) to be heavier along the time. Neither carcass yield and classification, nor ruminal pH, volatile fatty acids nor NH 3 -N concentrations were affected (p>0.050) by energy level. Total volatile fatty acids concentration tended (p=0.070) to be greater in heifers fed corn-based than wheat-based concentrates. No energy level x cereal type interactions were observed. These results indicate that high energy concentrates decreased feed intake and feed conversion but had minor effects on carcass performance. Cereal type had no effects on performance and ruminal fermentation and no interactions between cereal type and energy were detected.
Mostrar más

14 Lee mas

Network Induced Delay Models for Can Based Networked Control Systems Evaluation Edición Única

Network Induced Delay Models for Can Based Networked Control Systems Evaluation Edición Única

Abstract: Networked Control Systems (NCS) are a variation of traditional point- to-point control systems where sensors and actuators may be physically distributed and a serial common-bus communication network is used to exchange system information and control signals. Because all components use the same com- munication network, network-induced delays could make the system stochastic. The Quality of Control (QoC ) of each closed-loop system in a NCS is strongly affected by the network-induced delay produced by sensors and control signals. Controller Area Network (CAN ) is a popular real-time field-bus used for small- scale distributed environments such as automobiles. In CAN the delay exhibits a stochastic behavior and varies according to the network load. Since QoC is affected by delays, designing and evaluating a controller must take into account the effect of network-induced delays. This paper illustrates three models that play the role of classifiers and estimators of the network-induced delays; the models can estimate the network load and predict future time delay values. The models were built following a statistical approach using a continuous Hidden Markov Model, a black- box state space modeling approach using Recursive Multi-Layer Perceptrons, and a histrogram-based approach. Each approach was trained/tested using experimental data taken from a real CAN system with excellent results.
Mostrar más

125 Lee mas

TítuloFungal biocatalysts in the biofiltration of VOC polluted air

TítuloFungal biocatalysts in the biofiltration of VOC polluted air

The strain Cladosporium resinae ATCC 22711 was claimed to exhibit a minimal growth with a low biomass yield on benzene after a long period of incubation of several weeks, but further investigation with that strain would have been needed to confirm this finding ( Cofone et al., 1973). More recently, Phanerochaete chrysosporium was also shown to use and degrade 9.6 and 18.1% benzene in the case of strains ME-446 and BKM-F 1767, respectively ( Yadav and Reddy, 1993). Somewhat more information has recently been obtained on the biodegradation of substituted benzenes in fungi. A recent study showed that among 260 fungi screened from a culture collection, none appeared to be able to grow on toluene as sole carbon and energy source ( Prenafeta-Boldú et al., 2001). Despite this observation, experiments with new fungal isolates indicated that toluene seems to be the most easily biodegradable alkylbenzene in fungi ( Estévez et al., 2004, García-Peña et al., 2001, Prenafeta-Boldú et al., 2001 and Woertz et al., 2001). According to our present knowledge, fungi using xylenes as carbon and energy sources are scarce. Some strains of the white-rot fungus P. chrysosporium can degrade xylenes during primary metabolism, although biodegradation is only partial (<50%) and the level of mineralization is quite limited ( Yadav and Reddy, 1993). Very recently xylenes proved to be partly cometabolized by another fungal strain, that does not belong to the group of white-rot fungi, in presence of toluene or ethylbenzene as growth substrate ( Prenafeta-Boldú et al., 2002). Benzene rings with one single side chain seem to be much easier to metabolize than poly-substituted compounds in eukaryotes. The same is true in most prokaryotes ( Veiga et al., 1999). However, some fungi appeared to degrade n- alkylbenzenes with side chains containing at least four or more carbons, while they were unable to grow on benzene, toluene or ethylbenzene ( Fedorak and Westlake, 1986). Although fungi can degrade volatile aromatic pollutants, the capacity to degrade hydrocarbons is not a constant characteristic among specific fungal species, and such metabolic activity can therefore not be used in taxonomic studies ( Oudot et al., 1993), despite the fact that this has sometimes been suggested ( Nyns et al., 1968). In this paper, our interest will mainly focus on the group of alkyl- and alkenyl-benzenes, since they are important air pollutants and most of the information on the removal of those compounds by fungi is very recent. Studies on the removal of such hydrophobic compounds from polluted air by means of gas-phase bioreactors inoculated with fungi or yeast-like fungi were initiated hardly more than one decade ago ( Braun-Lüllemann et al., 1992, Cox et al., 1996a and Cox et al., 1997).
Mostrar más

26 Lee mas

Gas solubility and rheological behavior study of betaine and alanine based natural deep eutectic solvents (NADES)

Gas solubility and rheological behavior study of betaine and alanine based natural deep eutectic solvents (NADES)

increasing pressure and decreasing temperature. Solubility decrease with the increase of temperature can be explained with the kinetic energy of the gas molecules; as it is increased with the increasing temperature, gas molecules break the intermolecular bonds that are formed within the solute and gain higher inclination to escape from the solution. No hysteresis was observed during the solubility measurements, which eliminates the potential swelling effect of the liquids under such pressure conditions. Experimented solubility trends fit to absorption profile type III[52, 53]. However, solubility figures show that there is still an increasing trend in the solubility plot, which means there is still a potential for higher solubility in studied NADESs. Nevertheless, going beyond 50 bars would be practically challenging from both processing and economic reasons in large- scale applications, considering the viscosity limitations (explained in section 3.3). Solubility tests were performed at least 3 times on each of the NADESs and no significant change was observed on the performance of the gas solubility. At each solubility measurement, end-of-the-experiment vacuum measurements yielded the same mass reading as at the beginning of the experimental routine; which means no residual CO 2 (or N 2 ) remained in the sample at the end of the run. Thus, chemisorption is
Mostrar más

40 Lee mas

Impact of Organizational Inertia and Dynamic Capabilities on Educational Performance of the Charitable Societies and Its Impact on Mathematical Performance of Elementary At-Risk Students

Impact of Organizational Inertia and Dynamic Capabilities on Educational Performance of the Charitable Societies and Its Impact on Mathematical Performance of Elementary At-Risk Students

“La inercia es la fuerte persistencia de las estructuras y capacidades existentes. Para la supervivencia o el éxito de una organización, puede ser bueno o malo mantener una fuerte persistencia” (Wernerfelt, 1984, p. 173). Si el entorno y las condiciones son estables, el fenómeno de la inercia le da a la organización una sensación de estabilidad (Hannan & Freeman, 1984). Cuando la capacidad de una organización se vuelve rígida, muchas organizaciones de éxito son incapaces de detectarlo, ni siquiera cuando se enfrentan a una amenaza u oportunidad externa percibida, o de emprender alguna acción al respecto (Sull, 1999; Gilbert, 2005, 2006). En el presente estudio, los investigadores examinan la incidencia de la inercia organizativa en unos profesionales de la educación que imparten docencia en un grupo de escuelas a las que se ha encomendado la instrucción de una población de alumnos de educación primaria en situación de riesgo de Teherán (Irán). Estos estudiantes eran alumnos afganos que asistían a escuelas creadas por ONG y a los que les impartían docencia profesores con poca o ninguna experiencia en la enseñanza en los cursos reglados de educación primaria. Además, la investigación muestra que el mero contacto con los estudiantes no basta a la hora de crear la experiencia positiva necesaria para proporcionar la instrucción en un medio que encaje con los intereses y antecedentes de los alumnos (Morales, Sanhueza, Friz, & Riquelme, 2017). La experiencia con los estudiantes actuales sugiere que la convicción del personal educativo resulta clave para cambiar la inercia de aquellos. Los resultados del estudio en su totalidad se pueden consultar en Amiripour, Dossey, Shahvarani and Tabibi (2016).
Mostrar más

15 Lee mas

Comparison of the behavior of biofuel based on castor and sunflower oils

Comparison of the behavior of biofuel based on castor and sunflower oils

The increase in motor vehicles year after year in Colombia has generated a direct relationship with environmental contamination due to constant gas emissions; additionally, Price variation of oil has permitted considerable increase in the demand of ACPM [1], to the point of displacing gasoline consumption for passenger and cargo transportation in developing countries, which is why it is necessary to have an alternative of a biodiesel using renewable resources. Currently, some projects have been developed in Colombia to achieve clean production of biodiesel, which is a liquid hydrocarbon derived from plant and animal fats through a transesterification process based on the reaction of an oil or fat and an a half catalyzed alcohol [2]. Biodiesel has certain advantages compared to fossil diesel (oil). Some of these benefits include having non-toxic, biodegradable, as well as aromatic and sulfur-free fuels. Furthermore, its use notoriously lowers noxious gases from internal combustion engine exhausts by behaving as a fuel additive, thus, improving the amount of oxygen in the mix.
Mostrar más

7 Lee mas

APPLICATION OF SIO2 NANOPARTICLES AS PRETREATMENT ALLEVIATES THE IMPACT OF DROUGHT ON THE PHYSIOLOGICAL PERFORMANCE OF PRUNUS MAHALEB L. - Sociedad Argentina de Botánica

APPLICATION OF SIO2 NANOPARTICLES AS PRETREATMENT ALLEVIATES THE IMPACT OF DROUGHT ON THE PHYSIOLOGICAL PERFORMANCE OF PRUNUS MAHALEB L. - Sociedad Argentina de Botánica

Drought stress, as multidimensional abiotic stress, strongly affects growth, development, and yield of plants (Mahajan & Tuteja, 2005). Undoubtedly, understanding mechanisms that plants use to deal with drought stress are important. However, equally important are cultural methods enhancing natural drought tolerance (Sacala, 2009). Given that conventional fertilisers can have adverse effects on the environment and potentially on food quality, researchers are now investigating the potential use of nanotechnology to reduce the negative impact of abiotic stresses in plants (Asadzade et al., 2015; Chen & Yada, 2011; Haghighi & Pessarakli, 2013). Nanosciences have led to the development of a wide range of applications for enhancing of plant growth (Nair et al., 2010). Carbon-based, metal oxides, quantum dots, nano-sized polymers and biocomposites materials in plant science are being developed (Khot et al., 2012). Nanomaterials are materials with a particle size between 1 and 100 nm and implicate new physical, chemical and biological properties compared to bulk size materials (Monica & Cremonini, 2009). Also, some researchers think that absorption of nanoparticles in plants is greater than the same chemicals applied to the plant in bulk size (Braunack, 1995; Suriyaprabha et al., 2012). Although some recent studies on the effects of SiO 2
Mostrar más

14 Lee mas

Full PDF

Full PDF

This paper was prepared during my stay as a graduate student in the Departamento de Oceanografía at the Universidad de Concepción (UDEC). Therefore, I appreciate the support of CONICYT and the Graduate School of UDEC for the Scholarship awarded. The database used in this study is part of my thesis to obtain the title of biologist at the Universidad de Guaya- quil (Ecuador), which was conducted with the support of the Instituto Nacional de Pesca (INP) and the Fondo Ecuatoriano Populorum Progressio (FEPP). My gratitude to Yahira Pie- drahita (Directora – INP) for her support with funding for the publication of this manuscript. I thank also Jorge Alberto López-Rocha (CICI- MAR) and Roberto Licandeo (UDEC) for their valuable recommendations to the initial ver- sion of this manuscript. My thanks go to J.A. López-Rocha for providing growth estimation of Anadara from Mexico. Finally, especial thanks to Liliana Alencastro, Nikita Gaibor and Jennifer Nuñez for correction and editing of the English version, and also to the referees for their comments that improved this manuscript.
Mostrar más

12 Lee mas

Impact of acidification and protein fortification on thermal properties of rice, potato and tapioca starches and rheological behaviour of their gels

Impact of acidification and protein fortification on thermal properties of rice, potato and tapioca starches and rheological behaviour of their gels

The addition of egg albumin and soy protein isolate at 10% (by weight in the solid starch-protein mixtures) combined with a reduction of pH to 4.5 proved to be an efficient way to modify the thermal and rheological properties of rice, potato and tapioca starches and starch gels. Gels prepared at 120 °C were much weaker (lower consistency and more prone to break-down upon deformation) than those formed at 90 °C; the rice starch being the most sensitive to increasing gelification temperature and potato the most resistant. In general, proteins worked as structure enhancing agents at both temperatures; in gels prepared at 120ºC the strengthening effect was more pronounced. In contrast, acidification weakened the structure of these gels. It can be concluded that both pH and addition of exogenous proteins are useful approaches to modify the functional properties of gel-like starchy food products. The rheological observations made in this study could be helpful in attempting to modify gluten-free formulations, which are mostly based on non-wheat cereal or tuber starches to optimize the end-product quality attributes (texture, microstructure, thermal stability of autoclaved food products to extend their shelf life). Further studies are needed to clarify the role of acidification into heated starch-protein mixtures by employing a range of structure probing analytical techniques (calorimetry, various rheological tests, chromatography, different spectroscopies, etc.) to unravel the molecular interactions among the hydrocolloids involved and thereby fine tune end-product quality.
Mostrar más

20 Lee mas

CLIL and reading strategies worksheets to foster reading comprehension

CLIL and reading strategies worksheets to foster reading comprehension

In the same vein, McTaggart (1999) asserted that action research entails the examination of realities where the researcher creates and organizes actions to improve people’s conditions, which means that action research has a direct impact on the individuals who participate in this study. Likewise, Kemmis and McTaggart (1988) sustained that action research is grounded on a cycle that embraces five stages: Identifying a problem, developing a plan for improvement, implementing the plan, observing and documenting the effects of the plan, and reflecting on the effects of this plan. In this case, the problem identified was the students’ lack of strategies to understand written texts; and the plan to solve this issue was the design of appealing and contextualized materials based on reading strategies to improve the learners’ reading comprehension. Then, I implemented the materials and collected information concerning the the students’ attitudes and behaviors when working on the worksheets. Finally, I analyzed the effectiveness of the materials and their influence on the learners’ reading comprehension
Mostrar más

104 Lee mas

Achieving effective visitor orientation in European museums  Innovation versus custodial

Achieving effective visitor orientation in European museums Innovation versus custodial

In our work we are particularly concerned with clarifying what exactly is meant when referring to visitor related performance in museums. McMillan, et al. and Gainer and Padanyi [21,22] feel that the outcome of any marketing strategy applied to museums must be assessed in both financial and non-financial terms. Following on from these approaches, we consider two kinds of performance: economic and market. In addition to weighing up obtained revenue, the economic aspect must also take account of factors such as how to increase visitor numbers, boost the number of friends of the museum, generate funds through temporary exhibitions or create jobs. All of these economic goals are geared towards ensuring the museum’s survival and viability. For its part, the market dimension of performance refers to the benefits obtained by individuals, such as enhanced visitor interest, their satisfaction, loyalty or the museum’s image.
Mostrar más

33 Lee mas

Show all 10000 documents...