New dispersions of liquid crystals in polymer matrices with improved wear and scratch resistance.

New compositions of polymer-dispersed thermotropic liquid crystals for moving parts sliding against metals. Properties of the new materials are a function of the concentration and distribution of the liquid crystal in the polymer matrix and depend on the mixing and molding proceses.Composition and manufacturing processes of blends containing thermoplastic polymers with additives based on ordered fluids such as thermotropic liquid crystals dispersed in the polymer matrix in order to modify the surface and improve the friction and wear resistance of the material and its processability. With this technological offer we try to collaborate with licence agreement and comercial agreement with technical assistance.Control of the additive proportion and distribution within a surface layer. This new technology increases the autolubricating ability of the polymers in applications where a high wear and scratch resistance are essential. The liquid crystalline additives can be removed from the matrix by supercritical CO2 extraction, thus allowing complete reciclyng. The new materials are homogeneous with a composition gradient. The new compositions containing thermotropic liquid crystals with controlled distribution and ease of processing allow surface modification with friction and wear reduction without changing the bulk material propertiesAditivos de polímeros. Fricción, lubricación, desgaste. Propiedades de materiales

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Rheological behaviour and functionality of inulin-extra virgin olive oil-based mashed potatoes

Developing products having a high nutritional value and good storage stability during freezing is a challenge. Inulin (I) and extra virgin olive oil (EVOO) have interesting functional properties. The e?ect of the addition of I and EVOO blends at di?erent I:EVOO ratios (0:0, 0:60, 15:45, 30:30, 45:15, 60:0, 30:45 and 45:30) on the rheological, physical, sensory and structural properties of fresh and frozen ? thawed mashed potatoes formulated without and with added cryoprotectants was analysed and compared. Addition of I and EVOO (either alone or blended) reduced apparent viscosity and pseudoplasticity producing softer systems, indicating that both ingredients behave as soft ?llers. Samples with added I at the higher concentrations )1 (?45 g kg ) showed lower ?ow index and consistency, which is related to formation of smaller I particles; microphotographs indicated that gelling properties of I depended mostly upon processing. Frozen ? thawed samples were judged more acceptable and creamier than their fresh counterparts

Rheological behaviour and functionality of inulin-extra virgin olive oil-based mashed potatoes

Developing products having a high nutritional value and good storage stability during freezing is a challenge. Inulin (I) and extra virgin olive oil (EVOO) have interesting functional properties. The e?ect of the addition of I and EVOO blends at di?erent I:EVOO ratios (0:0, 0:60, 15:45, 30:30, 45:15, 60:0, 30:45 and 45:30) on the rheological, physical, sensory and structural properties of fresh and frozen ? thawed mashed potatoes formulated without and with added cryoprotectants was analysed and compared. Addition of I and EVOO (either alone or blended) reduced apparent viscosity and pseudoplasticity producing softer systems, indicating that both ingredients behave as soft ?llers. Samples with added I at the higher concentrations )1 (?45 g kg ) showed lower ?ow index and consistency, which is related to formation of smaller I particles; microphotographs indicated that gelling properties of I depended mostly upon processing. Frozen ? thawed samples were judged more acceptable and creamier than their fresh counterparts

Protein isolate and inulin: chemical, rheological and structural basis

Soy protein isolate is typical vegetable protein with health-enhancing activities. Inulin, a prebiotic no digestible carbohydrate, has functional properties. A mashed potato serving of 200 g with added soy protein isolate and inulin concentrations of 15?60 g kg provides from 3 to 12 g of soy protein isolate and/or inulin, respectively. Currently, no information is available about the possible texture-modifying effect of this non-ionizable polar carbohydrate in different soy-based food systems. In this study, the effect of the addition of soy protein isolate and inulin blends at different soy protein isolate: inulin ratios on the degree of inulin polymerization and the rheological and structural properties of fresh mashed and frozen/thawed mashed potatoes were evaluated. The inulin chemical structure remained intact throughout the various treatments, and soy protein isolate did not affect inulin composition being a protein compatible with this fructan. Small-strain rheology showed that both ingredients behaved like soft fillers. In the frozen/thawed mashed potatoes samples,0 addition of 30 : 30 and 15 : 60 blend ratios significantly increased elasticity (G value) compared with 0 : 0 control, consequently reducing the freeze/thaw stability conferred by the cryoprotectants. Inulin crystallites caused a significant strengthening effect on soy protein isolate gel. Micrographs revealed that soy protein isolate supports the inulin structure by building up a second fine-stranded network. Thereby, possibility of using soy protein isolate and inulin in combination with mashed potatoes to provide a highly nutritious and healthy product is promising

A rheological characterization of mashed potatoes enriched with soy protein isolate

The effect of the addition of soy protein isolate (SPI) (0, 15, 30, 45 and 60 g kg ) on viscoelastic properties, large deformation measurements and microstructure of fresh (FM) and frozen/thawed (F/TM) mashed potatoes was investigated. Rheological data showed weak gel behaviour for both FM and F/TM potatoes without and with added SPI together with a signi?cant decrease of system viscoelasticity (G and G ) with increasing SPI volume fraction, primarily attributed to the no interaction between the amylose/amylopectine matrix and the dispersed SPI particles or aggregates as revealed by scanning electron microscopy (SEM). Micrographs also showed that SPI formed white coarse aggregates. A freeze/thaw cycle produced a more signi?cant decrease in viscoelastic functions, due to superior aggregation of denatured SPI and reduced water activity. In F/TM samples, high correlations between small and large deformation measurements were found. Results may be useful for technological applications in SPI-enriched

Antiwear performance of ionic liquid+graphene dispersions with anomalous viscosity-temperature behavior

New dispersions of few-layers graphene (G) in 1-ethyl-3-methylimidazolium ([EMIM]) ionic liquids (ILs) with dicyanamide ([DCA]) or bis(trifluoromethylsulfonyl)imide ([TFSI]) anions have been obtained by mechanical mixing and sonication. IL+0.5 wt% G dispersions show constant viscosity values from 357K (for IL = [EMIM][DCA]) or from 385K (for IL = [EMIM][TFSI]) to 393K. IL + G dispersions with G > 0.5 wt% show linear viscosity increases with increasing temperature, from 306K (for [EMIM][DCA]+1 wt%G) and from 330K to 393K (for [EMIM][TFSI]+0.75 wt%G and [EMIM][TFSI]+1 wt%G). Addition of graphene improves the poor wear reducing performance of [EMIM][DCA], and prevents surface damage on steel when added to [EMIM][TFSI]. Graphene increases the load-carrying ability of ILs, forms a surface layer on the sliding path and retains wear debris, preventing the formation of large abrasive particles.Ministerio de Economía, Industria y Competitividad (MINECO, Spain), EU FEDER Program (Grant # MAT2017-85130-P) Este trabajo es resultado de la actividad desarrollada en el marco del Programa de Ayudas a Grupos de Excelencia de la Región de Murcia, de la Fundación Séneca, Agencia de Ciencia y Tecnología de la Región de Murcia (Grant # 19877/GERM/15) M.D. Avilés ha recibido una beca del MINECO (BES-2015-074836)

Texture perception determined by doy protein isolate and inulin addition in potato puree: links with mechanical and microstructural features

This study evaluated the effect of adding soy protein isolate (SPI) and long-chain perception, trained and untrained panel inulin (INL) blends with 10 different SPI : INL ratios on the textural, rheological and 17 microstructural properties of freshly made and frozen/thawed potato puree. All the potato puree samples were subjected to a sensory texture pro?le analysis and a 21 trained panel rated the intensity of six descriptors, while an untrained panel did the same on six selected frozen/thawed products. The main SPI : INL ratio effect remained signi?cant for all the descriptors evaluated, when the analysis of variance was applied considering the untrained assessors as random effects. However, only trained panel scores for creaminess corresponded well with untrained assessor. Rheological ?ow index values were linked with variations in perceived consistency, and geometric and surface textural attributes were explained by structural features such as the presence of INL crystallites and SPI coarse strands

Polifenoles de plantas comestibles como reprogramadores metabólicos en condiciones de glucolipotoxicidad

Las plantas representan una enorme fuente de compuestos con importantes propiedades terapéuticas. Concretamente, los polifenoles han sido ampliamente estudiados no sólo por su inherente capacidad antioxidante, sino además porque su gran diversidad estructural les hace partícipes en multitud de procesos biológicos. Debido a este carácter pleiotrópico, los polifenoles son idóneos candidatos como compuestos bioactivos en el tratamiento de enfermedades multifactoriales como la obesidad y sus patologías asociadas. No obstante, muchos estudios que han empleado modelos celulares se centran en los efectos biológicos de estos compuestos sin considerar la biotransformación que sufren cuando son ingeridos. Considerando aspectos sobre la bioactividad y la biodisponibilidad, el objetivo fundamental de la presente Tesis ha sido profundizar en los mecanismos moleculares de los metabolitos derivados de polifenoles de Hibiscus sabdariffa (HS), Lippia citriodora (LC) y Olea europaea, demostrando su implicación en la mejora de las alteraciones asociadas con la obesidad. Los resultados de la presente Tesis, obtenidos mediante el empleo de un modelo celular de adipocitos hipertróficos inducidos por alta glucosa, indican que los polifenoles y sus metabolitos pueden alcanzar dianas intracelulares revirtiendo las alteraciones metabólicas que ocurren en el tejido adiposo obeso, como el estrés oxidativo, la excesiva acumulación de triglicéridos, la disfunción mitocondrial y la inflamación. Asimismo, se ha visto que los polifenoles pueden mediar sus efectos modulando la expresión génica de proteínas implicadas en el metabolismo lipídico, como la sintasa de ácidos grasos (FASN) o el receptor activado por proliferadores de peroxisomas alfa (PPARα), y la actividad de proteínas como la quinasa activada por AMP (AMPK), un regulador clave del metabolismo energético que representa una diana terapéutica potencial en patologías metabólicas. Además, los estudios computacionales sugieren que algunos polifenoles pueden desempeñar su papel de manera específica modulando directamente la actividad de sus dianas. A pesar de su baja biodisponibilidad, los estudios de intervención en humanos confirman la eficacia de estos polifenoles cuando son consumidos de forma regular en periodos relativamente cortos. En un estudio llevado a cabo con voluntarias obesas y con sobrepeso, se ha demostrado que la ingesta de una combinación de HS y LC puede mejorar parámetros antropométricos y el perfil lipídico, y reducir la tensión arterial sistólica y el pulso cardíaco. Se postula que estos cambios pueden ser mediados por la modulación de AMPK a nivel del tejido adiposo o actuando directamente sobre el sistema cardiovascular. Los resultados de esta Tesis ofrecen un conocimiento global sobre los potenciales metabolitos responsables de la bioactividad de plantas, así como sus posibles dianas moleculares.Plants represent an enormous source of compounds with important therapeutic properties. Specifically, polyphenols have been widely studied not only because of their inherent antioxidant capacity, but also because their high structural diversity makes them participants in a multitude of biological processes. Due to this pleiotropic nature, polyphenols become suitable candidates as bioactive compounds in the treatment of multifactorial diseases such as obesity and its related diseases. However, many studies using cellular models focus on the biological effects of these compounds without considering the biotransformation they suffer when ingested. Based on bioactivity and bioavailability data, the main objective of this Thesis has been to deepen the molecular mechanisms of polyphenol-derived metabolites from Hibiscus sabdariffa (HS), Lippia citriodora (LC) and Olea europaea, demonstrating their implication on the amelioration of obesity-associated alterations. Using a hypertrophic adipocyte cell model induced by high glucose, the results of this Thesis indicate that polyphenols and their metabolites can reach intracellular targets reversing the metabolic alterations occurred in obese adipose tissue, such as oxidative stress, excessive triglyceride accumulation, mitochondrial dysfunction and inflammation. Likewise, it has been observed that polyphenols can mediate their effects through modulation of gene expression of proteins involved in lipid metabolism, such as fatty acid synthase (FASN) or peroxisome proliferator-activated receptor alpha (PPARα), and the activity of AMPactivated protein kinase (AMPK), a key regulator of energy metabolism that represents a potential therapeutic target in metabolic pathologies. In addition, computational studies suggest that some polyphenols may play their role through a direct modulation of the activity of their targets. Despite the low bioavailability, human intervention studies confirm the efficacy of these polyphenols when consumed regularly in relatively short periods. In a study carried out with obese and overweight volunteers, it has been shown that the intake of a combination of HS and LC can improve anthropometric parameters and lipid profile and reduce systolic blood pressure and heart rate. It is postulated that these changes can be mediated by the modulation of AMPK in adipose tissue or through a direct action on the cardiovascular system. The results of this Thesis offer an extensive knowledge about the potential metabolites responsible for the bioactivity of plants, as well as their possible molecular targets

Efecto de la adición de ingredientes funcionales en el comportamiento reológico y la textura de puré de patata (Cv. Kennebec) fresco y congelado

El interés creciente en encontrar alimentos precocinados congelados que se asemejen a productos naturales, capaces de superar un procesado con el menor daño, ha generado un aumento en el estudio de nuevos productos en este campo de la investigación. Las características de cada matriz alimentaria, la composición y estructura de los ingredientes, así como el efecto de las interacciones entre ellos, modifica la textura, estructura y las propiedades físicas y sensoriales del alimento, así como su aceptación por el consumidor. En este contexto, la investigación realizada en esta tesis doctoral se ha llevado a cabo en puré de patata considerado como una matriz alimentaria semisólida y se ha centrado en analizar los efectos de la concentración y modificación de la composición en las propiedades reológicas y de textura, en las propiedades físico-químicas y estructurales, así como en los atributos sensoriales de los purés de patata cuando a estos se le añaden diferentes ingredientes funcionales como fibra de guisante, inulina, aceite de oliva, aislado de proteína de soja, ácidos grasos omega 3 y/o sus mezclas. Para ello, se han realizado cuatro estudios donde se determinan las propiedades reológicas mediante ensayos dinámicos oscilatorios y en estado estacionario, los parámetros instrumentales de textura mediante ensayos de extrusión inversa y de penetración cónica, además de los cambios estructurales a través de cromatografía iónica con detector de pulsos amperométrico, cromatografía de gases con detector de ionización de llama y microscopía electrónica de barrido. Conjuntamente, se han evaluado los atributos sensoriales de los diferentes purés generando los descriptores que mejor definen la calidad sensorial del producto, utilizando un panel de jueces entrenados y valorándose la aceptación global de los nuevos productos mediante un panel de consumidores. En un primer estudio, el puré de patata natural congelado elaborado con crioprotectores se enriqueció con fibra dietética insoluble (fibra de guisante), fibra dietética soluble (inulina) y sus mezclas. La fibra de guisante influyó significativa y negativamente en la textura del puré de patata, percibiéndose en el producto un incremento de la dureza y de la arenosidad, mientras que la inulina produjo un ablandamiento del sistema. En un segundo estudio, el puré de patata natural fresco y congelado/descongelado elaborado con y sin crioprotectores, se enriqueció con fibra dietética soluble (inulina), aceite de oliva virgen extra y sus mezclas. La adición de estos dos ingredientes generó un ablandamiento de la matriz del sistema, produciéndose, sin embargo, un efecto sinérgico entre ambos ingredientes funcionales. La inulina tuvo un efecto más significativo en la viscosidad aparente del producto, mientras que el aceite de oliva virgen extra afectó más significativamente a la pseudoplasticidad, al índice de consistencia y a la viscosidad plástica del mismo. El proceso de congelación y descongelación utilizado favoreció la reducción del tamaño de las partículas de inulina haciéndolas imperceptibles al paladar, obteniéndose productos más cremosos y con mayor aceptabilidad global que sus homólogos frescos. En un tercer estudio, el puré de patata natural fresco y congelado/descongelado elaborado con crioprotectores se enriqueció con mezclas de fibra dietética soluble (inulina) y aislado de proteína de soja. Los resultados demostraron que el ciclo de congelación y descongelación realizado no afecta el grado de polimerización de la inulina. La estructura química de la inulina tampoco se vio afectada por la incorporación de la soja. El proceso de congelación/descongelación, así como la adición de concentraciones altas de inulina y bajas de aislado de proteína de soja, favorecen la disminución de la contribución de la componente viscosa en las propiedades viscoelásticas del puré de patata. La cremosidad fue el único atributo sensorial que presentó una correlación lineal significativa entre las puntuaciones otorgadas por panelistas entrenados y no entrenados. Por último, se elaboró un puré de patata natural fresco y congelado/descongelado optimizado con crioprotectores y enriquecido con la suma de ácido docosahexaenoico (DHA, C22:6 n-3) y ácido eicosapentaenoico (EPA, C20:5 n-3) y con ácido α-linolénico (ALA, C18:3 n-3) microencapsulados. El ciclo de congelación y descongelación no afectó al perfil de ácidos grasos del puré de patata. La adición de omega 3 procedente de aceites de lino y pescado microencapsulados mejora los indicadores nutricionales que definen la calidad de la grasa, obteniéndose un producto más saludable. ABSTRACT The growing interest in finding frozen precooked products that are like a natural product and capable of withstanding initial processing with minimum damage and remaining stable during preservation and reheating prior to consumption has generated an increase in studies of new products in this field of research. The characteristics of each food matrix, the composition and structure of the ingredients and the effect of interactions between them alter the texture, structure and physical and sensory properties of the food product and its acceptance by the consumer. In this context, the research conducted in this doctoral thesis was carried out on mashed potato, considered as a semi-solid food matrix, and focused on analysing the effects of concentration and modification of the composition of the mashed potato matrix on the rheological and textural properties, physicochemical and structural properties and sensory attributes of mashed potato when various functional ingredients are added to it, such as pea fibre, inulin, olive oil, soy protein isolate, omega 3 fatty acids and/or mixtures of these ingredients. Four studies were conducted for this purpose. Rheological properties were determined by oscillatory dynamic tests and stationary state tests, and instrumental texture parameters by backward extrusion and cone penetration tests. Structural changes were studied by ion chromatography with pulsed amperometric detector, gas chromatography with flame ionisation detector and scanning electron microscopy. The sensory attributes of the various mashed potato mixtures were evaluated by generating the descriptors that best defined the sensory quality of the products and using a panel of trained judges, and overall acceptance of the new products was evaluated by a panel of consumers. In the first study, frozen natural mashed potato incorporating cryoprotectants was enriched with insoluble dietary fibre (pea fibre), soluble dietary fibre (inulin) and mixtures of the two. Pea fibre had a significant negative influence on the texture of the mashed potato, producing an increase in hardness and granularity, whereas inulin produced a softening of the system. In the second study, fresh and frozen/thawed natural mashed potato prepared with and without cryoprotectants was enriched with soluble dietary fibre (inulin), extra virgin olive oil and mixtures of the two. The addition of these two ingredients generated softening of the matrix of the system, but a synergic effect between the two functional ingredients was produced. Inulin had a more significant effect on the apparent viscosity of the product, whereas extra virgin olive oil had a more significant effect on its pseudoplasticity, consistency index and plastic viscosity. The freezing and thawing process that was used contributed to a reduction in the size of the inulin particles, making them imperceptible to the palate and producing creamier products with greater overall acceptability than their fresh equivalents. In the third study, the fresh and frozen/thawed natural mashed potato incorporating cryoprotectants was enriched with mixtures of soluble dietary fibre (inulin) and soy protein isolate. The results showed that the freezing and thawing process that was performed did not affect the degree of polymerisation of the inulin. The chemical structure of the inulin was also not affected by the incorporation of soy. The freezing and thawing process and the addition of high concentrations of inulin and low concentrations of soy protein isolate favoured a decrease in the contribution of the viscous component to the viscoelastic properties of the mashed potato. Creaminess was the only sensory attribute that presented a significant linear correlation between the scores given by trained and untrained panellists. Lastly, fresh and frozen/thawed natural mashed potato optimised with cryoprotectants was prepared and enriched with the sum of docosahexaenoic acid (DHA, C22:6 n-3) and eicosapentaenoic acid (EPA, C20:5 n-3) and with α-linolenic acid (ALA, C18:3 n-3), microencapsulated. The freezing and thawing process did not affect the fatty acid profile of the mashed potato. The addition of omega 3 obtained from microencapsulated linseed and fish oils improved the nutritional indicators that define the quality of the fat, producing a healthier product