1000 resultados para Qualitat dels aliments
Resumo:
L’objectiu d’aquest projecte ha sigut analitzar la qualitat de l’aigua a la Conca fluvial d’Alinyà i esbrinar quins són els factors que la determinen. Per fer-ho s’han utilitzat els macròfits (mitjançant l’índex IM) com a bioindicadors de la qualitat dels boscos de ribera i de manera indirecta determinar la qualitat de l’aigua. Es conclou que els factors més influents en els resultats són: la maca de diversitat dels macròfits donada l’època de l’any del mostreig (a la tardor), l’augment de les masses forestals homogeneïtzant el paisatge, les fortes pluges d’enguany i la contaminació puntual al nucli urbà d’Alinyà.
Resumo:
Este artículo, presenta una propuesta de ecoetiqueta que evalúa la calidad de los espacios de interés natural. Debido a la inexistencia de una ecoetiqueta de servicios de estas características, se han estudiado antecedentes de certificados ecológicos de servicios y sistemas de evaluación de espacios naturales y urbanos. A partir de este estudio, se han evaluado 110 indicadores preexistentes, de los cuales se han adaptado 59 indicadores, 29 de cumplimiento obligatorio y 30 recomendables, divididos en tres flujos: Flujo Humano, Flujo Natural y Flujo de Gestión, y 17 vectores; con los cuales se ha elaborado un sistema de evaluación adaptado a esta ecoetiqueta. Con la determinación del reglamento y las condiciones generales para la concesión de la propuesta de ecoetiqueta, se ha realizado una Prueba Piloto en la Vall d’Alinyà (Provincia de Lérida) centrada en el Flujo Humano, verificando de forma positiva la aplicación de la certificación en este espacio. Los resultados indican una adecuación de más del 90% de los indicadores seleccionados, mientras que se ha observado, principalmente, deficiencias en los sistemas hídricos y energéticos de la Vall d’Alinyà. Por ello, se han elaborado una serie de propuestas de mejora.
Resumo:
The present study arose from the need to determine inorganic arsenic (iAs) at low levels in cereal-based food. Validated methods with a low limit of detection (LOD) are required to analyse these kinds of food. An analytical method for the determination of iAs, methylarsonic acid (MA) and dimethylarsinic acid (DMA) in cereal-based food and infant cereals is reported. The method was optimised and validated to achieve low LODs. Ion chromatography-inductively coupled plasma mass spectrometry (LC-ICPMS) was used for arsenic speciation. The main quality parameters were established. To expand the applicability of the method, different cereal products were analysed: bread, biscuits, breakfast cereals, wheat flour, corn snacks, pasta and infant cereals. The total and inorganic arsenic content of 29 cereal-based food samples ranged between 3.7-35.6 and 3.1-26.0 microg As kg-1, respectively. The present method could be considered a valuable tool for assessing inorganic arsenic contents in cereal-based foods.
Resumo:
Amino-N is preserved because of the scarcity and nutritional importance of protein. Excretion requires its conversion to ammonia, later incorporated into urea. Under conditions of excess dietary energy, the body cannot easily dispose of the excess amino-N against the evolutively adapted schemes that prevent its wastage; thus ammonia and glutamine formation (and urea excretion) are decreased. High lipid (and energy) availability limits the utilisation of glucose, and high glucose spares the production of ammonium from amino acids, limiting the synthesis of glutamine and its utilisation by the intestine and kidney. The amino acid composition of the diet affects the production of ammonium depending on its composition and the individual amino acid catabolic pathways. Surplus amino acids enhance protein synthesis and growth, and the synthesis of non-protein-N-containing compounds. But these outlets are not enough; consequently, less-conventional mechanisms are activated, such as increased synthesis of NO∙ followed by higher nitrite (and nitrate) excretion and changes in the microbiota. There is also a significant production of N(2) gas, through unknown mechanisms. Health consequences of amino-N surplus are difficult to fathom because of the sparse data available, but it can be speculated that the effects may be negative, largely because the fundamental N homeostasis is stretched out of normalcy, forcing the N removal through pathways unprepared for that task. The unreliable results of hyperproteic diets, and part of the dysregulation found in the metabolic syndrome may be an unwanted consequence of this N disposal conflict.
Resumo:
The reason for this study is to propose a new quantitative approach on how to assess the quality of Open Access University Institutional Repositories. The results of this new approach are tested in the Spanish University Repositories. The assessment method is based in a binary codification of a proposal of features that objectively describes the repositories. The purposes of this method are assessing the quality and an almost automatically system for updating the data of the characteristics. First of all a database was created with the 38 Spanish institutional repositories. The variables of analysis are presented and explained either if they are coming from bibliography or are a set of new variables. Among the characteristics analyzed are the features of the software, the services of the repository, the features of the information system, the Internet visibility and the licenses of use. Results from Spanish universities ARE provided as a practical example of the assessment and for having a picture of the state of the development of the open access movement in Spain.
Resumo:
Peer reviewed
Resumo:
Peer reviewed
Resumo:
Peer reviewed
Resumo:
Resveratrol has been shown to have beneficial effects on diseases related to oxidant and/or inflammatory processes and extends the lifespan of simple organisms including rodents. The objective of the present study was to estimate the dietary intake of resveratrol and piceid (R&P) present in foods, and to identify the principal dietary sources of these compounds in the Spanish adult population. For this purpose, a food composition database (FCDB) of R&P in Spanish foods was compiled. The study included 40 685 subjects aged 3564 years from northern and southern regions of Spain who were included in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Spain cohort. Usual food intake was assessed by personal interviews using a computerised version of a validated diet history method. An FCDB with 160 items was compiled. The estimated median and mean of R&P intake were 100 and 933 mg/d respectively. Approximately, 32% of the population did not consume RΠ The most abundant of the four stilbenes studied was trans-piceid (53·6 %), followed by trans-resveratrol (20·9 %), cis-piceid (19·3 %) and cis-resveratrol (6·2 %). The most important source of R&P was wines (98·4 %) and grape and grape juices (1·6 %), whereas peanuts, pistachios and berries contributed to less than 0·01 %. For this reason the pattern of intake of R&P was similar to the wine pattern. This is the first time that R&P intake has been estimated in a Mediterranean country.
Resumo:
L’ús de fitorreguladors com aclaridors químics en el cultiu del presseguer és una pràctica que no s’utilitza en la majoria d’explotacions comercials. Actualment l’aclarida es realitza de forma manual. Els assajos realitzats en dos varietats de presseguer, Zephyr i Fairlane, tenen per objectiu determinar l’eficàcia de l’aplicació d’àcid giberèl•lic (Ralex®) per a reduir la inducció de gemmes florals l’any següent a la seva aplicació. L’aplicació de 3,3 l/ha d’un formulat a base d’àcid giberèl•lic (Ralex®) en la primera quinzena de juliol ha reduït de forma significativa el nombre de flors en la varietat Zephyr, tot i que en Fairlane l’efecte no ha estat tant clar. Pel que fa a la qualitat dels fruits, val a dir que el tractament no ha mostrat, en aquest assaig, cap efecte de significació agronòmicament remarcable.
Resumo:
En aquest estudi es caracteritzen 15 varietats locals de l'Horta de Lleida i una de Tírvia (Pallars). S'estudien 8 varietats penjar, 2 de punxeta i 6 d'amanida. Per això, es descriu la germinació, l'estat fenològic, la part vegetativa i el fruit, la qualitat dels fruits i la conservació en postcollita. Totes aquestes característiques estan resumides en unes fitxes que identifiquen cada varietat, arribant a ser útils per a agricultors, tècnics i per a la comparació amb altres estudis similars. S'obtenen, a més, llavors de totes les varietats per cedir-les al Banc de Germoplasma de la ETESA.
Resumo:
Avui en dia la nanotecnologia té moltes aplicacions en la indústria alimentària, fet que podria aportar noves oportunitats en la mateixa. Tot i que les nanoemulsions contenen partícules amb un tamany de partícula d’entre 50 i 500 nanòmetres, la seva elevada àrea d’interfase implica unes característiques que podrien afavorir i presentar molts avantatges pel que fa a la bioaccessibilitat d’alguns compostos beneficiosos per a la salut. A més a més, també milloren moltes propietats físico-químiques de les emulsions (color, aspecte, viscositat etc), punt important per la fabricació de nous productes alimentaris atractius al consumidor.
Resumo:
The present study arose from the need to determine inorganic arsenic (iAs) at low levels in cereal-based food. Validated methods with a low limit of detection (LOD) are required to analyse these kinds of food. An analytical method for the determination of iAs, methylarsonic acid (MA) and dimethylarsinic acid (DMA) in cereal-based food and infant cereals is reported. The method was optimised and validated to achieve low LODs. Ion chromatography-inductively coupled plasma mass spectrometry (LC-ICPMS) was used for arsenic speciation. The main quality parameters were established. To expand the applicability of the method, different cereal products were analysed: bread, biscuits, breakfast cereals, wheat flour, corn snacks, pasta and infant cereals. The total and inorganic arsenic content of 29 cereal-based food samples ranged between 3.7-35.6 and 3.1-26.0 microg As kg-1, respectively. The present method could be considered a valuable tool for assessing inorganic arsenic contents in cereal-based foods.
Resumo:
Resveratrol has been shown to have beneficial effects on diseases related to oxidant and/or inflammatory processes and extends the lifespan of simple organisms including rodents. The objective of the present study was to estimate the dietary intake of resveratrol and piceid (R&P) present in foods, and to identify the principal dietary sources of these compounds in the Spanish adult population. For this purpose, a food composition database (FCDB) of R&P in Spanish foods was compiled. The study included 40 685 subjects aged 35-64 years from northern and southern regions of Spain who were included in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Spain cohort. Usual food intake was assessed by personal interviews using a computerised version of a validated diet history method. An FCDB with 160 items was compiled. The estimated median and mean of R&P intake were 100 and 933 mg/d respectively. Approximately, 32% of the population did not consume RΠ The most abundant of the four stilbenes studied was trans-piceid (53·6 %), followed by trans-resveratrol (20·9 %), cis-piceid (19·3 %) and cis-resveratrol (6·2 %). The most important source of R&P was wines (98·4 %) and grape and grape juices (1·6 %), whereas peanuts, pistachios and berries contributed to less than 0·01 %. For this reason the pattern of intake of R&P was similar to the wine pattern. This is the first time that R&P intake has been estimated in a Mediterranean country.
Resumo:
Selenium is recognised as an essential micronutrient for humans and animals. One of the main sources of selenocompounds in the human diet is vegetables. Therefore, this study deals with the Se species present in different edible sprouts grown in Se-enriched media. We grew alfalfa, lentil and soy in a hydroponic system amended with soluble salts, containing the same proportion of Se, in the form of Se(VI) and Se(IV). Total Se in the sprouts was determined by acidic digestion in a microwave system and by ICP/MS. Se speciation was carried out by enzymatic extraction (Protease XIV) and measured by LC-ICP/MS. The study shows that the Se content of plants depends on the content in the growth culture, and that part of the inorganic Se was biotransformed mainly into SeMet. These results contribute to our understanding of the uptake of inorganic Se and its biotransformation by edible plants.