Proyecto de fábrica artesanal de yogur de leche de oveja en el polígono industrial “San Antolín” (Palencia)

El presente proyecto consiste en la implantación de una fábrica artesanal de yogur de leche de oveja en el polígono industrial "San Antolín" , situado en la provincia de Palencia. Se procesan 60000 litros de leche de oveja al año para hacer yogures de150 g. La industria está diseñada con las instalaciones y la maquinaria necesaria para permitirla elaboración de tres tipos de yogur batido: natural, azucarado y con confitura de fruta.Grado en Ingeniería de las Industrias Agrarias y Alimentaria

Estudio de la incorporación de altos porcentajes de proteínas en productos sin gluten a base de cereales

Las proteínas, junto a carbohidratos y grasas, son macromoléculas que componen la base de la dieta humana. En los últimos años, la presencia de altos contenidos de proteína en productos se ha convertido en un reclamo de los consumidores. Se conoce que un mayor consumo de proteínas puede producir beneficios nutricionales para determinados grupos de población como deportistas, ancianos, etc. Además, la mayor sensación de saciedad que aportan los productos enriquecidos con proteínas los convierte en una buena opción para personas que quieren perder peso. Existen diferentes estudios que analizan el efecto de las proteínas en la funcionalidad de harinas y almidones, así como en las características de productos a base de cereales. Sin embargo, la mayor parte de estos trabajos estudian individualmente las proteínas, no comparan entre diferentes tipos de proteínas y los contenidos de proteínas adicionados son bajos (<15%). Además, algunos de estos estudios presentaron resultados contradictorios, y los diferentes requerimientos de agua de cada proteína podrían ser uno de los motivos. Por ello, el objetivo de la presente tesis fue evaluar el efecto de la incorporación de altos porcentajes de diferentes proteínas (arroz, patata, guisante, suero y huevo) en las características reológicas, físicas y sensoriales de productos sin gluten a base de cereales (galletas, panes, bizcochos y purés). Los tipos de proteína utilizados fueron elegidos en base a los resultados obtenidos en estudios previos realizados por el grupo de investigación. De esta forma, las proteínas seleccionadas presentan propiedades características y engloban la mayor parte de los tipos de proteínas disponibles (leguminosas, cereales, tubérculos, leche y huevo) para que los resultados puedan ser extrapolables a otras proteínas. Además, también se pretendió analizar diferencias entre las proteínas animales y las proteínas vegetales. En cuanto a los productos elegidos como matriz, se pretendió evaluar como la adición de proteínas puede influir en diferentes tipos de masas (batidas, cortas, fermentadas) y productos (horneados y mezclados en frío).Departamento de Ingeniería Agrícola y ForestalDoctorado en Ciencia e Ingeniería Agroalimentaria y de Biosistema

Assessing influence of protein source on characteristics of gluten-free breads optimising their hydration level

Most gluten-free products have lower protein content than their counterparts with wheat flour. The addition of exogenous proteins could not only be a good option to compensate for this reduction but also a tool to create gluten-free products rich in protein. However, the different water binding capacities of proteins modify dough rheology, which also affects bread volume. Therefore, this study aimed to analyse the incorporation of a high percentage (30%) of several proteins (rice, pea, egg white and whey protein) in gluten-free breads whose hydration levels were adjusted for each protein to achieve the maximum volume. In this way, the breads with vegetal proteins required a higher amount of water than the breads with animal proteins. Moreover, all enriched breads exhibited lower maximum volume values than control, and the ones with whey protein presented the lowest volumes overall. From these results, the rheological behaviour and characteristics (colour, texture and weight loss) of optimized doughs and breads were measured. The doughs with whey protein presented the highest G’ and G’’ values due to their low hydration level, and the ones with egg white protein were very watery. Regarding colour, the addition of protein led to darker crusts, with the ones with whey protein being the darkest. With respect to the control, breads with animal proteins exhibited higher hardness, especially with whey protein, while the ones with vegetal proteins did not present significant differences.Spanish Ministry of Economy and Competitiveness (Project AGL2014-52928-C2) and the European Regional Development Fund (FEDER

Influence of protein source on characteristics and quality of gluten-free cookies

Proteins are essential nutrients in the diet, with the recommended amount of daily protein consumption varying for people with different health status and activity level. Cookies could be an adequate carrier of proteins because of their great acceptability. The aim of this study was to analyse the effect of flour substitution with different types of protein (pea, potato, egg white and whey) in gluten-free cookies. Hydration properties, dough rheology, cookie characteristics (protein content, dimensions, texture) and sensory acceptability were studied. The hydration properties of mixtures with protein were lower than the control, with the exception of pea protein. As for results from rheological analysis, G´ and G” values for pea and potato protein were similar to the control, while egg white and whey protein had lower values. Regarding cookie characteristics, the addition of egg white and whey protein produced harder and wider cookies, respectively. The addition of potato protein yielded cookies with darker edges, but the incorporation of pea protein did not lead to any significant change in cookie parameters. Sensory evaluation showed that the addition of pea protein produced cookies with the same scores as the control sample, signifying that cookies with added pea protein had the best acceptability.Spanish Ministry of Economy and Competitiveness (Project AGL2014-52928-C2) and the European Regional Development Fund (FEDER

Assessing the Importance of Protein Interactions and Hydration Level on Protein-Enriched Gluten-Free Breads: a Novel Approach

The effect of starch substitution by 30% of different mixtures of egg white and pea proteins (100:0; 75:25; 50:50; 25:75; 0:100) was studied. The effect of hydration levels on specific volume was determined in order to later study the physical characteristics of different protein-enriched breads with an adjusted hydration level to achieve a specific volume similar to that of commercial wheat breads (5.5 ± 0.5 cm3/g). Hydration level needs to achieve this specific volume increased when increasing pea protein ratio. Control batter presented the highest elastic modulus, followed by the batter enriched with pea protein. Elastic modulus decreased progressively when increasing egg protein content. Same trend was observed for the viscous modulus. Differently, hardness was increased by the presence of egg protein, while decreased with the presence of pea protein. Breads with the same amount of both proteins showed no significant differences, compared to the control hardness. Regarding crumb structure, egg protein generated a uniform structure of small air bubbles that opened progressively when the proportion of pea protein was increased, until the same levels of both proteins were added, closing again with a higher pea protein content, but was not as close as when egg protein only was added. Key words:Spanish Ministry of Economy and Competitiveness (Project AGL2014-52928-C2)European Regional Development Fund (FEDER

Incorporation of gluten and hydrolysed gluten proteins have different effects on dough rheology and cookie characteristics

This study aims to establish how the substitution of wheat flour by high levels of gluten or hydrolyzed gluten proteins affect sugar-snap cookies properties. An increase in water binding capacity was observed when proteins were present. An increase in the dough elastic modulus was observed for gluten protein but it decreased when hydrolyzed gluten protein was used. Regarding the physical characteristics of the cookies, for the same protein percentage, the presence of gluten protein decreased spread ratio and increased hardness, while hydrolyzed gluten protein increased spread ratio and yielded darker cookies without modifying the hardness. As for sensory characteristics, taste was negatively influenced by hydrolyzed protein and visual acceptability was enhanced when gluten protein was present. Overall acceptability was decreased for the highest levels of hydrolyzed gluten protein. Nevertheless, the highest levels of gluten protein did not modify the acceptability.Spanish Ministry of Economy and Competitiveness (Project AGL2014-52928-C2) and the European Regional Development Fund (FEDER

Particle Size and Hydration Properties of Dried Apple Pomace: Effect on Dough Viscoelasticity and Quality of Sugar-Snap Cookies

Apple pomace (AP) is a by-product of the juice industry, rich in dietary fiber (45.06%), which is generated in large quantities. The objectives of the present work were to evaluate the effect of the particle size and the level of replacement with AP on the quality of sugar-snap cookies. Dehydrated AP was ground to three different particle sizes (d (4,3) = 362, 482, 840 μm) to substitute 15% and 30% of wheat flour in cookie formulations. The quality of dough and cookies was evaluated in terms of rheological properties, color, texture and global acceptability of the final product. When the AP particle size decreased, the water absorption properties (WHC, WBC) were higher (33 and 10 % respectively for the lowest and the highest particle size). For both replacement levels the smallest particle size (362 μm) led to the highest dynamic moduli of dough. The spread ratio (SR) of the cookies diminished when the particle size decreased (from 6.4 to 4.8 corresponding to AP840 and AP362 respectively). The lowest SRs were obtained for the 30% replacement level except for AP362. When employing AP with the largest particle size (840 μm) the cookies were less hard (48.7N). The addition of AP to sugar-snap cookies led to higher global acceptability scores than for control cookies. The sensory attribute that most differentiated the cookies with AP was their pleasant taste being the taste score always higher than the control one.Spanish Ministry of Economy and Competitiveness (Project AGL2014-52928-C2-2-R) and the European Regional Development Fund (FEDER) and the University of La Plata (Projects 11/X661 and 11/X771) and CONICET from Argentin

Influence of protein source on the characteristics of gluten-free layer cakes

The aim of this study was to examine the effect of four commercial proteins (pea, rice, egg white and whey) on the characteristics of gluten-free layer cakes. Rice flour was partially substituted with 15, 30 and 45% protein. Hydration properties, batter density and viscosity, cake characteristics (weight loss, specific volume, texture and colour) and consumer acceptability were analysed. In general, the addition of protein increased the viscosity of the batters, with higher protein contents exhibiting greater effects and with pea protein presenting the highest effect overall. The addition of egg white protein led to the hardest cakes (p<0.05) and whey protein, which also increased the cake hardness (p<0.05), gave rise to cakes with the highest specific volume. Both animal proteins increased the cake cohesiveness and springiness (p<0.05). On the contrary, pea and rice protein hardly modified hardness, colour and specific volume of cakes overall, but reduced their cohesiveness (p<0.05). Regarding sensory evaluation, all protein-enriched cakes presented lower acceptability with respect to control cake (p<0.05), but this effect was more pronounced when rice and egg white protein were added due to their taste, odour and texture. Whey protein cakes were, among the enriched samples, the ones with the highest acceptability

Estudio de mejora nutricional de galletas sin gluten con la incorporación de salvados modificados físicamente

La dieta sin gluten presenta deficiencias nutricionales en diferentes nutrientes entre los que destacan fibra alimentaria, minerales y vitaminas. El salvado de maíz es un subproducto de la industria alimentaria rico en nutrientes pero su inclusión en productos se ve dificultada por su dureza. El objetivo general del presente estudio es analizar el efecto de salvados de maíz tratados hidrotérmicamente en galletas con y sin gluten del tipo ―snap sugar‖. Se estudiaron las propiedades de hidratación de gel, absorción de agua y aceite de las mezclas, reología de las masas, características de las galletas (dimensiones, humedad, textura y color) y evaluación sensorial del producto final. Se observó que al adicionar salvado extrusionado, las harinas tienen una mayor capacidad de retención de agua y esto hace que las masas presenten una mayor consistencia. En lo que respecta a las galletas, la adición de salvado da lugar a galletas de menores dimensiones, dureza aceptable, y un color más oscuro, existiendo algunas diferencias entre tipos de salvado. Las valoraciones obtenidas en la evaluación sensorial concluyeron que la adición de salvado con germen daba como resultado galletas con una puntuación mayor que la muestra control. Esto permite obtener una galleta con un mayor valor nutricional pero sin modificar la aceptabilidad por parte del consumidor.Departamento de Ingeniería Agrícola y ForestalMáster en Calidad, Desarrollo e Innovación de Alimento

The effect of different protein addition on the rheological, physical and sensory characteristics of extruded maize-based purees

Over last years, consumers demand products that are easy to eat with health benefits. The use of extruded flours would be a good choice to reduce the preparation time. Moreover, high protein intakes would have a positive influence on the health of specific population groups. Therefore, this study aims to assess how the addition of vegetal (rice and pea) and animal (egg white and whey) proteins could influence the characteristics of purees prepared with extruded maize flour. Rheological behaviour, microstructure, viscosity, syneresis and sensory evaluation of purees were determined. The incorporation of vegetal proteins hardly modified the puree viscosity before and after heating, and reduced the syneresis after the freeze-thaw process. Animal proteins reduced the viscosity and G′–G′′ at 30ºC and increased them after heating, and also increased the syneresis after cooling and freezing. Finally, pea and egg white proteins hardly modified the overall acceptability while whey protein improved it.Spanish Ministry of Economy and Competitiveness (Project AGL2014-52928-C2)European Regional Development Fund (FEDER