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Caracterización fisicoquímica, aromática y sensorial de Fondillón, el vino más representativo de la Denominación de Origen Protegida Alicante
Get PDFPrograma de doctorado en Recursos y Tecnologías Agrarias, Agroambientales y AlimentariasEl Fondillón es un tipo de vino de Alicante único en el mundo; está reconocido por la Unión Europea en su base de datos E-bachus y es el núcleo de la Denominación de Origen Alicante (DOP Alicante). Está elaborado con uvas de la variedad Monastrell sobremaduradas en la cepa; por tanto, su contenido en alcohol (16 % v/v) procede exclusivamente de la uva, y necesita de un envejecimiento mínimo de 10 años. Al comienzo de esta tesis doctoral (octubre de 2018), sólo existía una publicación científica recogida en la base de datos SCOPUS sobre el Fondillón. Por tanto, no existía un conocimiento científico sobre qué hace especial a este vino; aunque cualquiera que haya probado este producto sabe que es único y diferente al resto de vinos. A partir de este momento, nos propusimos estudiar (i) el Fondillón y (ii) sus consumidores, para poder entender esta relación y así poder ver sus debilidades y fortalezas. Para ello establecimos unos objetivos específicos que incluían evaluar (i) las principales características fisicoquímicas del Fondillón, (ii) su perfil volátil, incluyendo los compuestos aromáticos activos (odor-active compounds), (iii) su perfil polifenólico, (iv) su perfil sensorial (definido por un panel entrenado y por un panel de consumidores), (v) el perfil tipo del consumidor actual, y (vi) marcadores claves para identificar posibles adulteraciones o fraudes en la comercialización de este vino. Con estos objetivos en mente, se comenzó a trabajar con el apoyo del Consejo Regulador de la DOP Alicante, y de dos bodegas BOCOPA y Monóvar (MGWines); sin embargo, hay que reseñar que para la realización de esta tesis doctoral no se ha contado con financiación de ningún tipo y que los recursos económicos han venido únicamente del grupo de investigación Calidad y Seguridad Alimentaria (CSA) de la Universidad Miguel Hernández de Elche. Se plantearon diversos experimentos encaminados al conocimiento progresivo del producto y de sus consumidores. Finalmente se publicaron 5 artículos en revistas internacionales en las que se estudiaron los parámetros que se detallan a continuación: Publicación 1 (Journal of Food Quality): características fisicoquímicas y primera aproximación al perfil volátil y sensorial de los tipos de Fondillón comercializados al comienzo de esta tesis doctoral. Este artículo es importante porque en él se desarrollaron el léxico y la ficha de cata para la evaluación sensorial descriptiva del Fondillón. Publicación 2 (Food Chemistry): compuestos aromáticos activos y perfil polifenólico. Esta publicación se realizó en colaboración con investigadores de la Çukurova University (Adana, Turquía), y es el núcleo de esta tesis doctoral. Publicación 3 (Agronomy): actividad antioxidante, características cromáticas, contenidos totales de taninos y antocianinas, y se comenzó a profundizar en el conocimiento del consumidor habitual de este vino. Publicación 4 (Foods): grado de satisfacción de los consumidores al respecto de los tipos de Fondillón comercializados y sobre sus principales atributos organolépticos. Además, se estudió el perfil tipo del consumidor actual de Fondillón. Publicación 5 (Beverages): desarrollo de un método para la identificación de muestras potencialmente adulteradas y que de ser comercializadas puedan suponer un fraude. Se estableció una huella digital inicial basada en la presencia de distintos parámetros a concentraciones específicas, para que por comparación se determine si las muestras bajo estudio son sospechosas de adulteración o no. Fruto de estos estudios y de las correspondientes publicaciones, el conocimiento sobre el Fondillón y sobre quién lo consume, cuándo lo consume y por qué lo consume ha mejorado; si bien, todavía son diversas las preguntas que tenemos y que orientarán nuestra línea de trabajo sobre el vino de la DOP Alicante. Algunas de las conclusiones principales que se han derivado de esta tesis doctoral son: Se ha desarrollado un léxico y una ficha de cata específicos para la descripción objetiva del Fondillón. Se tienen definiciones bastante coincidentes de Fondillón por parte de un panel entrenado y de un panel de consumidores: o Según los expertos “vino dulce, equilibrado (aunque con un marcado contenido alcohólico), con olor y aroma intensos en los que predominan los frutos maduros, los frutos secos, las notas tostadas de café, con madera bien integrada y con una persistencia muy larga” Según los consumidores “vino con buen equilibrio entre alcohol, dulzor y amargor, con notas florales, afrutadas y tostadas intensas, y con un prolongado y agradable postgusto” Se han identificado marcadores de envejecimiento: TDN, vitispirano, furfural, y benzaldehído. Se han identificado marcadores de autenticidad: fructosa, ácido acético, furfural, benzaldehído, vitispirano, TDN, etil octanoato, etil decanoato, entre otros. La totalidad de muestras evaluadas en esta tesis doctoral, cumplen con los requisitos para el Fondillón, según el pliego de condiciones de la DOP Alicante. Pero, para poder establecer un control sobre la autenticidad de las muestras en comercialización y detectar posibles fraudes, se ha desarrollado un modelo inicial (que necesita mejora en la cantidad de datos en que se basa, y en la automatización en la toma de decisiones), basado en los marcadores de autenticidad, anteriormente enumerados. Se ha identificado el perfil tipo del consumidor actual de Fondillón “hombre de entre 42 y 52 años, con un elevado nivel cultural/educativo, y con unos ingresos anuales entre 25.000 y 50.000 euros, y que bebe este vino principalmente en casa y en ocasiones especiales”. Además, se han identificado las principales razones para no consumir Fondillón que son: (i) el enorme desconocimiento del producto por parte del consumidor, (ii) su elevado precio, y (iii) que no es fácil de encontrar (ni en la cadena habitual de compra ni en los restaurantes). Toda la información generada en esta tesis doctoral nos permite tener un conocimiento inicial sobre el Fondillón y sobre quién lo consume. Sin embargo, todavía son muchas las incógnitas que envuelven a este tipo de vino de la DOP Alicante y que tenemos que seguir tratando de desvelar en un futuro cercano. Las principales líneas de trabajo a seguir son: Evaluar un mayor número de muestras de Fondillón de distintas bodegas, de distintas soleras, de distintas añadas, para poder confirmar el perfil volátil (marcadores de envejecimiento y de autenticidad). Pero, para ello es imprescindible la colaboración de todas y cada una de las bodegas que elaboran y comercializan Fondillón. Automatizar la toma de decisiones sobre la posible adulteración de muestras de Fondillón empleando técnicas de metabolómica (dirigida y no-dirigida) y métodos estadísticos más robustos. Ampliar el estudio sobre la aceptación de Fondillón y el perfil de consumidor a mercados internacionales. Y sin duda, la línea principal de investigación y trabajo es colaborar con las bodegas y la DOP Alicante en el desarrollo de estrategias conjuntas y basadas en la ciencia para la promoción del Fondillón, garantizando la calidad y especificidad del vino comercializadoFondillón is a unique type of Alicante wine in the world; it is recognized by the European Union in its E-bachus database and is the core of the Alicante Denomination of Origin (PDO Alicante). It is made with grapes of the Monastrell variety that are overripe on the vine; thus, its alcohol content (16% v/v) comes exclusively from the grape, and it needs a minimum aging period of 10 years. At the beginning of this doctoral thesis (October 2018), there was only one scientific publication on Fondillón gathered in the SCOPUS database. Therefore, there was no scientific knowledge about what makes this wine special; although anyone who has tried this product knows that it is unique and different from other wines. From this moment on, we set out to study (i) Fondillón and (ii) its consumers, to understand this relationship and thus be able to see its strengths and weaknesses. For this, we established specific objectives that included evaluating (i) the main physicochemical characteristics of Fondillón, (ii) its volatile profile, including the odor-active compounds, (iii) its polyphenolic profile, (iv) its sensory profile (defined by a trained panel and by a panel of consumers), (v) the typical profile of the current consumer, and (vi) key markers to identify possible adulterations or fraud in the marketing of this wine. With these objectives in mind, work began with the support of the Regulatory Council of the DOP Alicante, and two wineries BOCOPA and Monóvar (MGWines); however, it should be noted that no funding of any kind has been received for the completion of this doctoral thesis and that the economic resources have come solely from the Food Quality and Safety (CSA) research group of the Miguel Hernández University of Elche. Various experiments aimed at the progressive knowledge of the product and its consumers were proposed. Finally, 5 articles were published in international journals in which the parameters detailed below were studied: Publication 1 (Journal of Food Quality): physicochemical characteristics and the first approach to the volatile and sensory profile of the types of Fondillón commercialized at the beginning of this doctoral thesis. This article is important because in it the lexicon and tasting sheet/questionnaire for the descriptive sensory evaluation of Fondillón were developed. Publication 2 (Food Chemistry): odor-active compounds and polyphenolic profile. This publication was carried out in collaboration with researchers from Çukurova University (Adana, Turkey), and is the core of this doctoral thesis. Publication 3 (Agronomy): antioxidant activity, chromatic characteristics, total tannin and anthocyanin contents, and began to deepen the knowledge of the regular consumer of this wine. Publication 4 (Foods): degree of consumer satisfaction regarding the types of Fondillón marketed and its main organoleptic attributes. In addition, the profile of the current consumer of Fondillón was studied. Publication 5 (Beverages): development of a method for the identification of potentially adulterated samples that, if sold, could imply fraud. An initial fingerprint was established based on the presence of different parameters at specific concentrations, so that by comparison it can be determined whether the samples under study are suspicious of adulteration or not. As a result of these studies and the corresponding publications, knowledge about Fondillón and who consumes it, when it is consumed and why it is consumed has improved; Although, there are still various questions that we have and that will guide our line of work on PDO Alicante wine. Some of the main conclusions that have been derived from this doctoral thesis are: A specific lexicon and tasting sheet have been developed for an objective description of Fondillón. There are fairly consistent definitions of Fondillón by a trained panel and a panel of consumers: o According to the experts, "sweet, balanced wine (although with a marked alcoholic content), with an intense smell and aroma in which ripe fruits, dried fruits, and toasted notes of coffee predominate, with well-integrated wood and a very long aftertaste”. According to consumers, "a wine with a good balance between alcohol, sweetness and bitterness, with intense floral, fruity and toasted notes, and a long and pleasant aftertaste". Aging markers have been identified: TDN, vitispirane, furfural, and benzaldehyde. Authenticity markers have been identified: fructose, acetic acid, furfural, benzaldehyde, vitispirane, TDN, ethyl octanoate, ethyl decanoate, among others. All the samples evaluated in this doctoral thesis meet the requirements for Fondillón, according to the specifications of the DOP Alicante. But, in order to establish control over the authenticity of the samples being sold and detect possible fraud, an initial model has been developed (which needs improvement in the amount of data on which it is based, and in decision-making automation), based on the authenticity markers, listed above. The typical profile of the current consumer of Fondillón has been identified as “a man between 42 and 52 years of age, with a high cultural/educational level, and with an annual income between 25,000 and 50,000 euros, and who drinks this wine mainly at home and in special occasions". In addition, the main reasons for not consuming Fondillón have been identified, which are: (i) the enormous lack of knowledge of the product on the part of the consumer, (ii) its high price, and (iii) that it is not easy to find it (neither in shops nor in restaurants). All the information generated in this doctoral thesis allows us to have an initial knowledge about Fondillón and who consumes it. However, there are still many unknowns that surround this type of PDO Alicante wine and that we want to continue trying to reveal in the near future. The main lines of work to be followed are: Evaluate a greater number of Fondillón samples from different wineries, from different soleras, and from different vintages, to confirm the volatile profile (aging and authenticity markers). But, for this, the collaboration of all wineries producing and marketing Fondillón is essential. Automate decision-making on the possible adulteration of Fondillón samples using metabolomics techniques (directed and non-directed) and more robust statistical methods. Expand the study on the acceptance of Fondillón and the consumer profile to international markets. And without a doubt, the main line of research and work is to collaborate with the wineries and the DOP Alicante in the development of joint strategies based on science for the promotion of Fondillón, guaranteeing the quality and specificity of the wine markete
Evaluación de la actitud y los hábitos de consumo de los consumidores sobre el chocolate negro en tableta
Get PDFLa mayor parte del consumo del cacao se hace en forma de chocolate. El chocolate es un dulce de consumo habitual en los hogares españoles y se puede definir como un producto que se obtiene al mezclar la pasta y la manteca de cacao con el azúcar, pudiéndose añadir otros ingredientes. El objetivo de este trabajo es conocer la actitud y los hábitos de consumo de los consumidores sobre el chocolate negro en tableta a través de una encuesta en línea, en la que se formulan distintas preguntas relacionadas con las preferencias del consumidor a la hora de comprar chocolate, la frecuencia de consumo, la razón principal por la que lo hacen, etc. En los resultados se aprecia una inclinación hacia el chocolate puro con distintos porcentajes de cacao resultando este de gran éxito entre los consumidores pese a su relativa reciente introducción. Se concluye la investigación sabiendo que los consumidores recurren al chocolate por mero placer, especialmente en las tardes, y que optan por un perfil amargo e intenso sabor a cacao.The majority of cocoa beans that are consumed is in the form of chocolate. Chocolate is a sweet consumed regularly in Spanish homes and it can be defined as a product resulted of mixing the paste and the butter of cocoa beans with sugar, although other ingredients can be added. The current investigation aims to know the behavior and the consumption habits regarding dark chocolate as well as the frequency they consume it or the reasons for it. The results show a tendency to choose dark chocolate with different percentages of cocoa being, therefore, very successful among consumers taking into account its recent introduction to the general public. The investigation concludes that a great amount of people eat chocolate for pleasure, especially in the afternoon, and they prefer a bitter and intense flavor of cocoa rather a sweet one
Evaluación del efecto del agente leudante en el contenido en hidroximetilfurfural en bizcocho
Get PDFEl hidroximetilfurfural (HMF) se forma por la descomposición térmica de azúcares, y su presencia en productos horneados puede suponer un riesgo para la salud humana, por este motivo la industria alimentaria necesita desarrollar estrategias para mitigar su formación. Diferentes factores, como la temperatura, pH y humedad, así como el tiempo de horneado afectan a la formación de este compuesto. El objetivo principal de este trabajo es, determinar el contenido en HMF en productos horneados comerciales del tipo bizcocho y en bizcochos elaborados de forma tradicional y evaluar sus características de humedad, color y pH. Este primer paso nos orientará sobre el contenido en HMF en bizcochos comerciales. En segundo lugar, ensayar sobre una formulación básica de bizcocho, diferentes agentes leudantes (soda, y soda combinada con ácidos orgánicos) para evaluar su efecto en la generación de HMF. El HMF se determinó por cromatografía líquida de alta resolución (HPLC) con un detector de UV a 285 nm. En bizcochos comerciales no es tan común el uso de ácidos orgánicos junto con los agentes leudantes como en la elaboración casera de bizcochos. Se observa que, la presencia de ácidos orgánicos en la formulación, principalmente ácido tartárico, contribuye a una mayor generación de HMFHydroxymethylfurfural (HMF) is formed by the thermal decomposition of sugars, and its presence in baked products can pose a risk to human health, for this reason the food industry needs to develop strategies to mitigate its formation. Different factors, such as temperature, pH and humidity, as well as the baking time can affect the formation of this compound. The objective of this work is, firstly, to determine the content of HMF in commercial baked products of the sponge cake type and in traditionally made sponge cakes to evaluate their moisture, color, and pH characteristics. This first step will provide reference values of commercial products. Second, to test different leavening agents (soda, and soda combined with organic acids) on a basic sponge cake formulation to evaluate their effect on the generation of HMF and the profile of organic acids, humidity, and color of the sponge cake. HMF will be determined by high performance liquid chromatography (HPLC) with a UV detector at 285 nm. In commercial sponge cakes, the use of organic acids together with leavening agents is not as common as in home-made sponge cakes. The results show that the presence of organic acids increased the formation of HMF especially when tartaric acid was use
Scheduling Regulated Deficit Irrigation with Leaf Water Potential of Cherry Tomato in Greenhouse and its Effect on Fruit Quality
No full text22 páginas.- 6 figuras.- 6 tablas.- 41 referencias.- (This article belongs to the Special Issue Future of Irrigation in Agriculture)The tomato cultivated surface is one of the most important surfaces in the world. This crop needs a sufficient and continuous supply of water during vegetative growth. Therefore, production may be at risk in warm and water-scarce areas. Therefore, the implementation of irrigation alternatives such as regulated deficit irrigation (RDI) is of great importance to reduce the use of water and improve the production of the quality of tomatoes. The objective of this work was to evaluate the deficit irrigation scheduling using plant water status as a tool in deficit irrigation. Experimental design was a randomized design with four replications per treatment. Two irrigation treatments were applied: Control (125% of crop evapotranspiration (ETc)) and Regulated Deficit Irrigation (RDI). This latter treatment considered different threshold values of midday leaf water depending on crop phenological stage. No differences were observed in yield, with RDI treatment being more efficient in the use of irrigation water than the control. Besides, RDI tomatoes presented, in general, greater weight, size, Total soluble solids (TSS), sugars, antioxidant activity, lycopene, β-Carotene, and redder color with more intense tomatoes flavor. Finally, it might be said that RDI strategy helped to reduce 53% of irrigation water and to improve the nutritional, functional, and sensory quality of tomatoes.Peer reviewe
Effect of Aging Vessel (Clay-<i>Tinaja</i> versus Oak Barrel) on the Volatile Composition, Descriptive Sensory Profile, and Consumer Acceptance of Red Wine
Get PDFConsumers look for unique wines, offering pleasant experiences. Wine producers need to open new markets and are targeting countries with fewer traditions in drinking red and complex wines, such as Poland, Russia and Germany. The use of less popular aging vessels (e.g., clay-tinajas) will help in creating unique wines. The aim of this study was to evaluate the effect of the aging vessel on the volatile and sensory profiles and consumer acceptance of red wine in Spain and Poland (model of potential new markets). Three wines were studied: (i) wine A, aged in a clay-tinaja with non-permeable coating); (ii) wine B, aged in clay-tinaja without coating; and (iii) wine C, aged in oak barrels (control). The key families in the volatile profiles were esters (wines B and C) and organic acids and terpenes (wine A). Wine A was described as sour and bitter, wine B had a distinctive mineral note, and wine C had a complex profile with typical wood notes. Finally, wines C and A were the preferred ones for Spanish and Polish consumers, respectively. Clay-tinaja wine A can be a good option to introduce clay-tinaja wines in Polish and similar markets because it is a unique product and fulfills the sensory demands/habits of Polish consumers
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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