In vitro digestibility of highly concentrated methylcellulose O/W emulsions: Rheological and structural changes

The changes in structure during the digestion of highly concentrated methyl cellulose (MC) O/W emulsions and of hydrated MC were investigated. The effect of human saliva and in vitro stomach digestion was attributed to a dilution effect, rather than to pH or pepsin activity. After in vitro intestine incubation, a decrease in viscoelasticity and an increase in fat globule size were observed. The fat released after the digestion of the MC emulsion was 49.8% of the initial fat, indicating the existence of a big physical impediment. In comparison with an O/W whey protein emulsion with fat content equal to the fat released during the MC emulsion digestion, a 12% reduction in free fatty acid formation was found, which indicates that the decrease in fat bioaccessibility in the MC emulsion should be attributed not only to a physical effect against fat release but also to a further impediment related to the fat digestion process. Fat released quantification informs about the physical retention of fat in the emulsion matrix structure. Enzymes may not act if fat is not released and solubilized. Free fatty acid quantification is the real indicator of fat digestion, but contrary to the total fat released, it is affected by a wide variety of enzymatic factors, which should be considered for the correct comparison of systems of different properties, for example systems where the amount of fat release during the digestion may be different or initially unknown.Ministerio Economia y Competitividad of the Spanish Government for financial support (project AGL2015-68923-C2-1-R)Peer reviewe

COVID-19 outbreaks in a transmission control scenario: challenges posed by social and leisure activities, and for workers in vulnerable conditions, Spain, early summer 2020

Severe acute respiratory syndrome coronavirus 2 community-wide transmission declined in Spain by early May 2020, being replaced by outbreaks and sporadic cases. From mid-June to 2 August, excluding single household outbreaks, 673 outbreaks were notified nationally, 551 active (>6,200 cases) at the time. More than half of these outbreaks and cases coincided with: (i) social (family/friends’ gatherings or leisure venues) and (ii) occupational (mainly involving workers in vulnerable conditions) settings. Control measures were accordingly applied

Proceso innovador de fabricación de alimentos rebozados congelados que evita la etapa de prefritura industrial

Tesis doctoral presentada para lograr el título de Doctor por la Universidad de ValenciaLa etapa de prefritura es una de las más problemáticas del proceso de fabricación industrial de alimentos rebozados. Así mismo durante esta etapa el alimento rebozado absorbe una cantidad importante de aceite. La presente tesis doctoral describe un nuevo proceso de fabricación de alimentos rebozados congelados que evita la etapa de prefritura. Se basa en la capacidad de gelificación térmica de la Metilcelulosa (MC) y consiste en sustituir la etapa de prefritura del proceso tradicional por una etapa de coagulación en agua a 70ºC (desarrollo de una consistencia suficiente para la manipulación) y una de impacto térmico aplicable con un horno microondas, convencional o por un sistema de infrarrojos (bloqueo de la termoreversibilidad y estabilidad a cualquier temperatura). Las propiedades reológicas y microrestructurales de las pastas con MC desarrolladas se estudian y se compararan con las de una pasta convencional. Así mismo el proceso innovador se aplica a la fabricación de anillas de calamar rebozadas y sus características se comparan con las obtenidas ingredientes con funcionalidades diversas en los productos rebozados tradicionales ejercen sobre las características de las pastas y de las anillas de calamar obtenidas. Las pastas con MC presentaron una consistencia, una capacidad de retención de agua y una densidad de artefacto eutéctico en las microfotografías obtenidas por Cryo- Sem claramente superior a 5 que a 25ºC, lo que indica un mayor despliegue del hidrocoloide a menor temperatura y que se traduce en una potenciación de la capacidad de gelificación de la pasta a menor temperatura. A 15ºC los espectros mecánicos se correspondieron con un gel débil; a 60ºC los espectros se correspondieron con la estructura de un gel más fuerte.Peer reviewe

Use of Milk Fat/Cellulose Ether Emulsions in Spreadable Creams and the Effect of In Vitro Digestion on Texture and Fat Digestibility

© 2020 by the authors.This study investigated the texture properties and fat digestibility of new spreadable chocolate creams formulated with an emulsion composed of milk fat and a cellulose ether as a fat source. The spreadability was analysed at 20 °C and compared with a commercial spreadable cream formulated with palm fat. Structural changes in the creams after the in vitro oral and gastric digestion stages were evaluated; lipid digestibility was determined by titration with NaOH during intestinal digestion. Spreadability tests showed the spreads were similar. After oral digestion, the commercial spread showed an increase in extrusion force because of flocculation induced by saliva, an effect not observed in spreads with cellulose ether. Digestibility determination showed lower values for the reformulated spreads. Therefore, milk fat-cellulose ether based emulsions offer an alternative to achieve reformulated spreadable creams, with physical properties similar to those of commercial products but providing reduced fat content and lower lipid digestibility, without compromising the quality of the final product.This work was funded by grant RTI-2018-099738-B-C21 from the Spanish Ministry of Economy, Industry and CompetitivenessPeer reviewe

Establishing the function of proteins on the rheological and quality properties of rice based gluten free muffins

The incorporation of proteins has been long established in the bakery industry to obtain enriched products, but they also take active part on the making process of sweet baked goods. This study was focused on assessing the role of proteins on the rheology and quality of wheat free muffins by using rice flour. Six rice based formulations were used: one without added protein (No-Protein) and five with different protein sources: soy protein isolate (SPI), pea protein isolate (PPI), egg white protein (EWP), casein (C), and for comparing purposes vital wheat gluten (VWG) was included. Proteins effects were established by evaluating the rheological behaviour of batters measuring the storage modulus (G') and the loss modulus (G'), and the technological characteristics of the muffins obtained (specific volume, colour, and texture). The addition of SPI, PPI and C significantly (P<0.05) increased G', but this was not modified in batters containing EWP. Casein and EWP increased the specific volume of the muffins. SPI did not have effect on hardness, springiness, cohesiveness, chewiness, and resilience of the muffin, while PPI containing muffins were softer and springier. The overall results indicated that both the rheological properties of the batters and the technological characteristics of the muffin are dominated by the presence of the type of protein used in the formulations. Therefore the source of protein included in the formulation is fundamental to ensure the proper texture and other technological properties of these products. © 2013 Elsevier Ltd.Financial support of Spanish Scientific Research Council (CSIC), the Spanish Ministry of Economy and Sustainability (Project AGL2011-23802), and the GeneralitatValenciana (Project Prometeo 2012/064). M.E. Matos would like to thank predoctoral grant by the Council of Scientific and Humanistic Development of University Central of Venezuela (Caracas, Venezuela).Peer Reviewe

Fabricación y aplicación de emulsión sustituta de grasa

La presente invención se refiere a una emulsión comestible libre de ácidos grasos trans, que comprende un aceite vegetal, un éter de celulosa con capacidad de termogelificar y agua, capaz de reemplazar completamente el contenido de grasa de un producto alimentario, como por ejemplo una galleta, así como el procedimiento de obtención de la emulsión. Es asimismo, objeto de la presente invención una masa para la obtención de un alimento que comprenda dicha emulsión. Además, la presente invención también se refiere al uso, tanto de la emulsión como de la masa, en aplicaciones alimentarias.Peer reviewedConsejo Superior de Investigaciones Científicas (España)A1 Solicitud de patente con informe sobre el estado de la técnic

Optimization of Xanthan and Locust Bean Gum in a Gluten-Free Infant Biscuit Based on Rice-Chickpea Flour Using Response Surface Methodology

© 2020 by the authors.Incorporation of xanthan gum and locust bean gum in rice flour supplemented by chickpea flour was used to obtain a good quality of nutritionally enriched biscuit for celiac children. Response surface methodology (RSM) was applied to optimize the levels of xanthan and locust bean gum added to the composite gluten-free flour. Analysis was based on the rheological (hardness and viscoelastic) characteristics of the dough and specific volume, water activity, and hardness of the biscuit. The results revealed that the regression and variance analysis coefficients related to the rheological and physical properties of dough and biscuit under the influence of independent variables were sufficient for an adequate and well-fitted response surface model. Linear terms of variables significantly affect most of the dough and biscuit parameters, where the xanthan gum effect was found to be more pronounced than locust bean gum. Interaction terms showed a significant positive effect on the specific volume of the biscuits and a negative effect on the water activity. However, the interactive effect of gums did not significantly affect the rheological parameters of the dough. Optimized conditions were developed to maximize the specific volume of biscuit and minimize water activity and biscuit hardness, while keeping hardness and viscoelastic properties of the dough in range. Predicted responses were found satisfactory for both rheological and physical characteristics of dough and biscuit.This research was funded by the Ministère de l’Enseignement Supérieur et de la Recherche Scientifique. Université des frères MENTOURI- Constantine for finantial support to author S. Benkradi (Programme de formation residentielle à l’etranger (PNE)).Peer reviewe

Development and quality of rice flour-based gluten-free muffins

Gluten is the key protein complex that is responsible for the elastic characteristics of wheat dough contributing to the appearance and crumb structure of many baked goods. However, an increasing number of individuals are suffering from celiac disease (CD), the life-long intolerance to the gluten fraction of wheat, rye and barley. The increasing demand for gluten free products has favoured the design of numerous gluten free bakery products which intended to mimic the quality characteristics of wheat bakery products. The aim of this study was to design sweet formulation for obtaining rice flour muffins based on a traditional Spanish recipe, but formulations were eggs-free and lactose-free. The effect on different levels of xanthan gum as structuring agent in this product was tested. Quality of gluten-free muffins regarding their physicochemical characteristics (specific volume, moisture content, and colour), texture analysis (TPA) and image analysis (number of cells and total area) of the crumbs were evaluated. The addition of xanthan gum increased the volume of the gluten-free muffins, but high concentrations (0.7%) induced the opposite effect. Additionally, the structural analysis of the crumbs (number of cells and total area) discriminated between the muffins tested. The results obtained in this study showed the potential of developing gluten-free muffins based on rice flour, presenting good structural characteristics with the addition of xanthan gum on their formulations.Peer Reviewe

Rheological and microstructural behaviour of xanthan gum and xanthan gum-Tween 80 emulsions during in vitro digestion

The rheological, texture and microstructure properties of xanthan gum (XG) water solutions and XG emulsions, with and without Tween 80, were investigated and related to the emulsion fat lipolysis during in vitro digestion. The effect of digestion on the rheological properties of XG aqueous dispersions and XG-containing emulsions was quite different. The viscoelastic moduli G′ and G’’ of XG aqueous dispersion decreased after stomach digestion, while an increase was found in the XG emulsion without Tween 80. The viscoelasticity results were explained by the microstructure observations, where fat coagulation in the stomach in vitro model (pH 2.5 and pepsin) is observed in the absence of Tween 80, associated with the weaknesses of the XG structure at acidic pH. In all the systems, a decrease in the viscoelastic properties is observed after intestine digestion. In comparison to control emulsions without XG, the XG emulsions partially resist the digestion process, decreasing the quantity of free fatty acids (FFA). In the presence of Tween 80, the decrease in fat digestion was enhanced, the XG-Tween 80emulsion being the one with the lowest fat digestibility. These results may have important implications for the design of satiating food and food with low fat digestibility.The authors would like to thank the Spanish Ministry of Economy and Competitiveness (MEC) for financial support (Project AGL2015-68923-C2-1-R).Peer reviewe