Academic literature on the topic 'Garrofon'

A method is described that allows the development of an empirical approach to quantify synergistic interactions and their variations with shear rate. The approach is based on the definition of a viscous synergism index, Iv. The method is applied to xanthan-locust bean gum gels, and an equation is developed for relating the synergism index to shear rate, γ, and the locust bean gum/xanthan gum concentration ratio, z. The value of at which that function has a maximum, IMV, is calculated. This value of z provided an estimation of the proportion of gums at which maximum synergism occurs. A decreasing exponential dependence of these IMV on γ is shown. The influence of the addition of a fixed proportion of a third gum (NaCMC) is also analyzed. The results obtained for the higher γ values are analogous to those of other authors.

IntroductionPatients requiring invasive mechanical ventilation via an artificial airway experience sudden voicelessness placing them at risk for adverse outcomes and increasing provider workload. Infection control precautions during the COVID-19 pandemic, including the use of personal protective equipment (eg, gloves, masks, etc), patient isolation, and visitor restrictions may exacerbate communication difficulty. The objective of this study is to evaluate the acceptability of a codesigned communication intervention for use in the adult intensive care unit when infection control precautions such as those used during COVID-19 are required.Methods and analysisThis three-phased, prospective study will take place in a medical surgical ICU in a community teaching hospital in Toronto. Participants will include ICU healthcare providers, adult patients and their family members. Qualitative interviews (target n: 20–25) will explore participant perceptions of the barriers to and facilitators for supporting patient communication in the adult ICU in the context of COVID-19 and infection control precautions (phase 1). Using principles of codesign, a stakeholder advisory council of 8–10 participants will iteratively produce an intervention (phase 2). The codesigned intervention will then be implemented and undergo a mixed method acceptability evaluation in the study setting (phase 3). Acceptability, feasibility and appropriateness will be evaluated using validated measures (target n: 60–65). Follow-up semistructured interviews will be analysed using the theoretical framework of acceptability (TFA). The primary outcomes of this study will be acceptability ratings and descriptions of a codesigned COmmunication intervention for use during and beyond the COVID-19 PandEmic.Ethics and disseminationThe study protocol has been reviewed, and ethics approval was obtained from the Michael Garron Hospital. Results will be made available to healthcare providers in the study setting throughout the study and through publications and conference presentations.

Background:Nutritional follow-up as part of the integral attention for patients living with rheumatoid arthritis (RA) has been limited due to the COVID-19 pandemic. It made necessary to implement a remote monitoring for the care of the patients and to evaluate the outcomes of the changes in the care model.Objectives:To identify the effects of the telemonitoring intervention within the pandemic scenario and the outcomes of the traditional face-to-face nutrition consultation.Methods:A retrospective analysis of health records and the administrative data base of the patient’s follow-up, between 2019 and 2020, was developed at the arthritis specialized center of the Santa Fe de Bogotá Foundation in Bogotá, Colombia. The outcomes measured include the number of visits per year and the proportion of patients who attend their nutritional follow-up by telemonitoring in 2020 vs patients attending to face-to-face nutrition consultation. Differences in the Body Max Index (BMI) and the changes based on eating habits, defined by the quality of food consumption per day, were also measured.Results:A total of 212 patients from 2020 and 179 from 2019 were analyzed; An increase of 61.5% in the number of consultations, using nutritional telemonitoring per year, was identified in 2020 (n=412) compared to 2019 (n=255). In patients followed from 2019 to 2020, 13% (10/77) experienced an increase of more than 2 units of their BMI, while 22% (17/77) showed a decrease; in 2% of patients was not possible to evaluate their current weight; in the same way, 49% (103/212) in 2020 showed a positive change in their feeding habits compared with a 12% (21/179) in 2019. 135 new patients were recruited for nutritional telemonitoring 2020.Conclusion:Nutritional telemonitoring to follow-up patients with RA has increased considerably in terms of consultations per year and changes in the feeding habits. However, more evaluation is required for this model.References:[1]Melanie J Martin, Nora Ng, Laura Blackler, Toby Garrood, P227 Remote monitoring of patients with RA: a user-centred design approach, Rheumatology, Volume 59, Issue Supplement_2, April 2020, keaa111.221, https://doi.org/10.1093/rheumatology/keaa111.221[2]Principio del formularioDisclosure of Interests:None declared

[ES] Durante siglos de cultivo en la Península Ibérica después de su introducción en el siglo XVI, las judías se adaptaron a nuevos entornos, evolucionando numerosas variedades locales. Se evaluaron cultivares españoles locales de Phaseolus lunatus (frijol lima) y su resistencia a la salinidad, en dónde se expusieron las plantas a varios tratamientos de sal, con el fin de evaluar el efecto de la salinidad en el crecimiento y el rendimiento del cultivo. Se observó que el estrés salino redujo el peso fresco de los órganos aéreos, lo que permitió clasificar los cuatro genotipos según su tolerancia a la salinidad. la prolina aumentó en todos los cultivares, más notablemente en el cv. VPH-79, con las concentraciones absolutas más altas registradas en los cultivares más tolerantes a la sal. Estos hallazgos indican que P. lunatus es moderadamente tolerante a la sal y que sus principales mecanismos para adaptarse al estrés salino son el mantenimiento de altas concentraciones de K+ y la acumulación de prolina en las hojas. Por otra parte, se analizaron en invernadero 24 genotipos locales de P. vulgaris de España durante dos temporadas consecutivas. De cada genotipo, se cultivaron cinco plantas y se caracterizaron (17 rasgos cuantitativos y 15 cualitativos) utilizando los descriptores del IBPGR. Los resultados obtenidos indican una alta variabilidad para la mayoría de los rasgos, especialmente los relacionados con el rendimiento y sus componentes. Además, se analizaron las respuestas a los tratamientos por déficit hídrico y estrés salino, en cuanto a inhibición del crecimiento y contenido de prolina foliar (Pro), en 47 genotipos de Phaseolus vulgaris de diferentes orígenes. Para la mayoría de las variables de crecimiento analizadas y Pro, los efectos del cultivo, el tratamiento y sus interacciones fueron altamente significativos (p<0.001); los rasgos morfológicos de las raíces, el diámetro del tallo y el número de hojas se debieron principalmente a una variación incontrolada, mientras que la variación del peso fresco y el contenido de agua de los tallos y las hojas fue inducida claramente por el estrés. Bajo las condiciones experimentales, los efectos promedio del estrés salino sobre el crecimiento de las plantas fueron relativamente más débiles que los del déficit hídrico. . Pro, por su parte, fue la única variable que mostró una correlación negativa con todos los parámetros de crecimiento, pero particularmente con los de tallos y hojas mencionados anteriormente, como lo indican los coeficientes de correlación de Pearson y los PCA. Se propone el uso de Pro como un marcador bioquímico adecuado para exámenes simples, rápidos y a gran escala de genotipos de judía, para excluir los más sensibles, aquellos que acumulan concentraciones más altas de Pro en respuesta a tratamientos de estrés hídrico o salino. Asimismo, se han analizado las respuestas a la salinidad en seis cultivares de judía común: cuatro variedades locales de España y dos líneas experimentales de Cuba. La prolina fue usada para clasificar la tolerancia de los cultivares, Las concentraciones de azúcares solubles totales variaron con los tratamientos y entre los genotipos, pero fue difícil evaluar su papel en la tolerancia al estrés de las plantas analizadas. Los cambios en el contenido de malondialdehído (MDA) no indicaron peroxidación de la membrana inducida por sal como resultado del estrés oxidativo secundario; en consecuencia, no se detectó acumulación de compuestos fenólicos totales y flavonoides, como mecanismo de defensa antioxidante. Estos resultados destacan la confiabilidad del uso de prolina como marcador bioquímico del estrés salino en judía y la importancia del mecanismo relacionado con el transporte de potasio a las hojas para conferir tolerancia al estrés a algunos cultivares de judía.
[CA] Durant segles de cultiu a la Península Ibèrica després de la seva introducció en el segle XVI, les mongetes es van adaptar a nous entorns, evolucionant nombroses varietats locals. Es van avaluar conreessis espanyols locals de garrofó (fesol llima) i la seva resistència a la salinitat, a on es van exposar les plantes a diversos tractaments de sal, per tal d'avaluar l'efecte de la salinitat en el creixement i el rendiment de l'cultiu. Es va observar que l'estrès salí va reduir el pes fresc dels òrgans aeris, el que va permetre classificar els quatre genotips segons la seva tolerància a la salinitat. la prolina augmentar en tots els conreessis, més notablement en el cv. VPH-79, amb les concentracions absolutes més altes registrades en els conreessis més tolerants a la sal. Aquestes troballes indiquen que P. lunatus és moderadament tolerant a la sal i que els seus principals mecanismes per adaptar-se a l'estrès salí són el manteniment d'altes concentracions de K + i l'acumulació de prolina en les fulles. D'altra banda, es van analitzar en hivernacle 24 genotips locals de P. vulgaris d'Espanya durant dues temporades consecutives. De cada genotip, es van conrear cinc plantes i es van caracteritzar (17 trets quantitatius i 15 qualitatius) utilitzant els descriptors de l'IBPGR. Els resultats obtinguts indiquen una alta variabilitat per a la majoria dels trets, especialment els relacionats amb el rendiment i els seus components. A més, es van analitzar les respostes als tractaments per dèficit hídric i estrès salí, pel que fa a inhibició de l'creixement i contingut de prolina foliar (Pro), en 47 genotips de Phaseolus vulgaris de diferents orígens. Per a la majoria de les variables de creixement analitzades i Pro, els efectes de l'cultiu, el tractament i les seves interaccions van ser altament significatius (p <0.001); els trets morfològics de les arrels, el diàmetre de la tija i el nombre de fulls es van deure principalment a una variació incontrolada, mentre que la variació de l'pes fresc i el contingut d'aigua de les tiges i les fulles va ser induïda clarament per l'estrès. Sota les condicions experimentals, els efectes mitjana de l'estrès salí sobre el creixement de les plantes van ser relativament més febles que els de el dèficit hídric. . Pro, per la seva banda, va ser l'única variable que va mostrar una correlació negativa amb tots els paràmetres de creixement, però particularment amb els de tiges i fulles esmentats anteriorment, com ho indiquen els coeficients de correlació de Pearson i els PCA. Es proposa l'ús de Pro com un marcador bioquímic adequat per a exàmens simples, ràpids i a gran escala de genotips de mongeta, per excloure els més sensibles, aquells que acumulen concentracions més altes de Pro en resposta a tractaments d'estrès hídric o salí. Així mateix, s'han analitzat les respostes a la salinitat en sis conreessis de mongeta comú: quatre varietats locals d'Espanya i dues línies experimentals de Cuba. La prolina va ser usada per a classificar la tolerància dels conreessis, Les concentracions de sucres solubles totals van variar amb els tractaments i entre els genotips, però va ser difícil avaluar el seu paper en la tolerància a l'estrès de les plantes analitzades. Els canvis en el contingut de malondialdehid (MDA) no van indicar peroxidació de la membrana induïda per sal com a resultat de l'estrès oxidatiu secundari; en conseqüència, no es va detectar acumulació de compostos fenòlics totals i flavonoides, com a mecanisme de defensa antioxidant. Aquests resultats destaquen la fiabilitat de l'ús de prolina com a marcador bioquímic de l'estrès salí en jueva i la importància de l'mecanisme relacionat amb el transport de potassi a les fulles per conferir tolerància a l'estrès a alguns conreessis de mongeta.
[EN] During centuries of cultivation in the Iberian Peninsula after their introduction in the 16th century, beans adapted to new environments, evolving numerous landraces.In this study was also evaluated the resistance to salinity of several local Spanish cultivars of Phaseolus lunatus L. (lima bean). Plants were subjected to various salt treatments and growth and biochemical parameters were determined. It was observed that salt stress reduced the fresh weight of aerial organs, which allowed us to classify the four genotypes according to their tolerance to salinity. In addition, proline increased in all cultivars, most notably in cv. VPH-79, with the highest absolute concentrations recorded in the most salt tolerant cultivars. These findings indicate that P. lunatus is moderately salt tolerant and that its main mechanisms for adapting to salt stress are the maintenance of high K+ concentrations and proline accumulation in leaves. In studies conducted in this research project, 24 landraces of P. vulgaris from Spain were analyzed in greenhouses during two consecutive seasons. From each genotype, five plants were grown and characterized for 17 quantitative and 15 qualitative traits using IBPGR descriptors. . The results obtained indicate high variability for most of the traits, especially those related to yield and its components. On the other hand, this study analyzed the responses to water deficit and salt stress treatments, in terms of growth inhibition and leaf proline (Pro) content, in 47 Phaseolus vulgaris genotypes of different origins. For most of the growth variables analyzed and Pro, the effects of cultivar, treatment and their interactions were highly significant (p <0.001); root morphological traits, stem diameter and number of leaves were mainly due to uncontrolled variation, whereas variation in fresh weight and water content of stems and leaves was clearly induced by stress. Under our experimental conditions, the average effects of salt stress on plant growth were relatively weaker than those of water deficit. . Pro, in turn, was the only variable that showed a negative correlation with all growth parameters, but particularly with those of stems and leaves mentioned above, as indicated by Pearson's correlation coefficients and PCAs. We propose the use of Pro as a biochemical marker suitable for simple, rapid, large-scale screening of bean genotypes to exclude the most sensitive, those that accumulate higher concentrations of Pro in response to water or salt stress treatments. In addition, responses to salinity were analyzed in six common bean cultivars: four local varieties from Spain and two experimental lines from Cuba. Proline was used to rank the relative tolerance of the cultivars. Concentrations of total soluble sugars varied with treatments and among genotypes, but it was difficult to assess their role in stress tolerance of the plants tested.. Changes in malondialdehyde (MDA) content did not indicate salt-induced membrane peroxidation as a result of secondary oxidative stress; consequently, accumulation of total phenolic compounds and flavonoids, as an antioxidant defense mechanism, was not detected. These results highlight the reliability of the use of proline as a biochemical marker of salt stress in common beans and the importance of the mechanism related to potassium transport to leaves in conferring stress tolerance to some common bean cultivars.
Arteaga Castillo, SM. (2021). Cultivos para el cambio climático: selección y caracterización de variedades de judía (Phaseolusvulgaris L.) y Phaseolus lunatus tolerantes a la sequía y salinidad [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/168450
TESIS

Orientador : Maria Amelia Chaib Moraes
Tese (doutorado) - Universidade Estadualde Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Este trabalho teve como principais objetivos: estudar o método de acidificação direta para o processamento do queijo Mozarela de leite de búfala, em comparação com o processo tradicional, avaliando-se as características físicas, químicas e sensoriais dos queijos obtidos, e verificar a aplicabilidade do Perfil Livre para avaliação de apenas duas amostras. Foram realizados três processamentos para cada método. As etapas de coagulação e fermentação foram as que diferiram do método de acidificação direta para o tradicional. Com a diminuição do tempo de coagulação de aproximadamente 50 minutos para 5 minutos e ausência da etapa de fermentação no método de acidificação direta, que durou 4 horas no método tradicional, observou-se uma redução de aproximadamente 60% do tempo de processamento, isto é, de 8 para 3 horas. Os rendimentos obtidos para o queijo Mozarela elaborado pelo método de acidificação direta foram maiores que os obtidos no tradicional, em tomo de 18,00 e 17,30%, respectivamente. O queijo elaborado pelo método de acidificação direta apresentou menores teores de proteína e maiores de umidade e, conseqüentemente, menor teor de sólidos totais em relação ao método tradicional (p<0,05). Os teores de gordura, cinzas e cálcio dos dois tipos de queijo não apresentaram diferenças significativas (p>0,05). As amostras de cada processamento foram avaliadas com 3 repetições. Os dados foram analisados pela Análise Procrustes Generalizada, mostrando que houve uma alta repetibilidade dos provadores, assim como entre os processamentos. As amostras foram diferenciadas principalmente pelos atributos de aparência e textura. O queijo Mozarela elaborado pelo método tradicional apresentou cor mais branca e maior firmeza e fibrosidade. O queijo elaborado pela acidificação direta, apresentouse mais macio, com maior umidade e coloração esverdeada. Para o teste de aceitação, 50 provadores não treinados avaliaram as amostras utilizando escala hedônica de 9 pontos. Não houve diferença significativa (p < 0,05) na aceitação das amostras, com médias 6,68 e 6,26 para o método de acidificação direta e método tradicional, respectivamente. As distribuições dos valores de aceitação foram muito similares para as duas amostras, com tendência a valores mais altos para a amostra obtida.pela acidificação direta. Relacionando esses resultados com os do Perfil Livre, conclui-se que apesar das amostras apresentarem diferenças marcantes, estas praticamente não influenciaram na aceitabilidade dos queijos. Foram também realizadas avaliação instrumental de cor e textura. A apálise de cor, foi realizada por reflexão de luz, por meio de um espectrofotômetro CONCOR 1500 Plus sob o iluminante C. Observou-se que a Mozarela obtida pela acidificação direta apresentou menores valores de luminosidade e maiores valores de verde em relação a tradicional. Para a análise de textura foi utilizado o texturômetro TA-XT2 Texture Analyser e observou-se que o queijo elaborado pelo método de acidificação direta apresentou-se mais macio, com uma redução de 48% no valor da força máxima. Analisando-se todos os resultados em conjunto, verifica-se que eles foram concordantes, pois o maior teor de umidade do queijo obtido pela acidificação direta observado na análises fisicas e químicas, foi também destacado na análise sensorial. Esse fato pode estar relacionado com a menor firmeza desse queijo, obtida como resultado tanto da análise instrumental como da sensorial. Também, houve concordância entre as medidas sensoriais e instrumentais de cor, revelando uma coloração esverdeada no queijo obtido pela acidificação direta, apesar desta característica não ter afetado a aceitabilidade do produto. Pode-se concluir que o método do Perfil Livre foi eficiente neste estudo. Seus resultados apresentaram alta repetibilidade e foram concordantes com os obtidos através das análises instrumentais
Abstract:The main objectives of this work were to study the direct acidification method for the processing of Mozarela cheese made from buffalo milk and compare it to the traditional method, evaluating the physical-chemical and sensory characteristics of the cheeses, and to verify the applicability of the Free Choice Profile for the evaluation of two samples. Three processing batches for each method were done. Coagulation and fermentation steps were the ones that differed between the direct acidification and traditional method. With the coagulation time reduced from approximately 50 to 5 minutes and absence of the fermentation step in the direct acidification method, that lasted approximately 4 hours in the traditional method, a reduction of approximately 60% of the used time was observed (from 8 to 3 hours). Yields obtained for the Mozarela cheese elaborated by the direct acidification method were higher than those obtained with the traditional method, around 18,00 and 17,30%, respectively. Cheese elaborated by the acidification method presented lower protein and higher humidity contents and, consequently, lower contents of total solids in relation to the traditional method (p>0,05). There were no significative differences (p>0,05) between the two types of cheeses for fat, ash and calcium levels. Samples of each processing were evaluated with 3 repetitions. Data were analyzed using the Generalized Procrustes Analysis. Results showed a high repeatability of the tasters, as well as between the processing. The samples were differentiated mainly by the appearance and texture attributes. The Mozarela cheese elaborated by direct acidification was softer, with higher humidity and presented a greenish color. The Mozarela cheese elaborated by traditional method has higher firmness and fibrousness. For the acceptance test, 50 non-trained tasters evaluated the samples with a 9 points hedonic scale. Results showed no significant difference (p<0,05) in the acceptance of the samples, with means of 6,68 and 6,26 for the direct acidification method and traditional method, respectively. The distribution of the acceptance values were very similar for both samples, with a tendency of higher values for the sample obtained by direct .acidification. Relating these results with the ones of the Free Choice Profile, it was Goncluded that although the samples presented marked, differences, these practicaliy did not influence the acceptability of the cheeses. Color and textural instrumental evaluation were also done. Color analysis were done by light reflection, using a CONCOR 1500 Plus spectrophotometer under C iluminant. The Mozarela cheese obtained by direct acidification presented a lower I luminosity value and higher green values in relation to the traditional. For the: texture analysis, a TA-XT2 Texture Analyzer texturometer was used and showed that the cheese elaborated by the direct acidification method was softer, with .a 48% reduction in the maximum force value. Analyzing ali the results, it was verified that ali of them had a good degree of agreement, because the higher content of humidity of the cheese obtained by the direct acidification analysis detected in the physical and chemical analysis was also detected in the sensory analysis. This fact can be related with the lower firmness of this cheese, obtained as a result of the instrumental and sensory analysis. There was also agreement between the sensory and instrumental color measurements, revealing a greenish color of the cheese obtained by direct acidification, a1though this characteristic did not affect the product acceptability. It can be conc1uded that the Free Choice Profile method was efficient in this study. Its results presented a high repeatability and agreed with the ones obtained using instrumental analysis
Doutorado
Doutor em Tecnologia de Alimentos

Actualment hi ha un especial interès pels compostos fenòlics dels aliments en àmbits de la nutrició, salut i medicina en base a diferents evidències que suggereixen que poden actuar com a potents antioxidants i/o moduladors de funcions biològiques claus en els mamífers. Paral·lelament, hi ha una demanda per part dels consumidors en quant a la informació dels aliments que s'ingereix, de les necessitats nutricionals així com de la millora de salut. Tots aquest conceptes juntament amb la definició imminent de la legislació europea en relació als perfils nutricionals i les al·legacions de propietat de salut porta implícit la disponibilitat de metodologies adequades per a la caracterització dels aliments. Per a donar resposta a una necessitat actual, l'interès d'aquesta tesis es centra en el desenvolupament de metodologies que permetin la identificació, verificació, quantificació i eficiència de compostos bioactius. Aquestes metodologies representen eines de treball que han de facilitar la formulació de nous aliments amb al·legacions de propietat de salut.
Per assolir aquests objectius, aquest treball va seleccionar dues fonts d'origen vegetal per a l'obtenció i avaluació de compostos fenòlics: el cacau i la garrofa. Els extractes de cacau són una font reconeguda de compostos fenòlics, principalment procianidines, i alcaloides. En el present estudi l'interès es centra bàsicament en ampliar la seva caracterització fenòlica, avaluar la seva capacitat antioxidant i l'efecte del processament tecnològic. Per assolir aquesta fita es va treballar amb diversos productes derivats del processament del cacau, sent aquests la fava, el nib, el licor de cacau i el pols de cacau.
L'acceptació dels productes elaborats amb el cacau és universal i darrerament s'han publicat estudis que confirmen que els fenols presents en la xocolata, procedents del cacau, resulten beneficiosos per a la salut. Tot i això, l'alt contingut en greixos saturats, així com la riquesa en sucres són factors limitadors alhora d'aconsellar un increment del consum en una dieta equilibrada.
Per aquest motiu es va proposar com a font alternativa la farina de garrofa, per a presentar un contingut baix de greixos i ser una font rica de fibra.
El fruit d'aquest treball es recull en el desenvolupament de tècniques cromatogràfiques que permeten identificar i quantificar el perfil fenòlic dels derivats del cacau i de la farina de garrofa (UPLC-MS/MS) així com tècniques espectrofotomètriques que es poden emprar com a eines ràpides de selecció d'extractes polifenòlics (Folin-Ciocalteau i l'assaig de Vainillina). Al mateix temps, s'han optimitzat dues metodologies d'extracció que han permès l'obtenció d'extractes rics en compostos fenòlics d'ambdues fonts d'estudi. Els extractes polifenòlics obtinguts han estat avaluats en termes de la capacitat antioxidant a nivell in-vitro aplicant el mètode DPPH i posant a punt i aplicant el mètode ORAC. Finalment, s'ha avaluat l'estabilitat dels compostos fenòlics de les matrius d'estudi sota condicions fisiològiques del procés de digestió humana mitjançant el desenvolupament d'un model de digestió gastrointestinal in-vitro.
En la actualidad hay un especial interés por los compuestos fenólicos de los alimentos en los ámbitos de la nutrición, la salud y la medicina preventiva, basado en diferentes evidencias que indican que los compuestos fenólicos pueden actuar como potentes antioxidantes y/o moduladores de funciones biológicas claves en los mamíferos. Paralelamente, hay una demanda por parte de los consumidores de información acerca de los alimentos que se consumen y de las necesidades nutricionales, así como de la mejora de la salud. Todos estos conceptos, junto con la definición inminente de la legislación europea en relación a los perfiles nutricionales y a las alegaciones de propiedades saludables, lleva implícito la necesidad de disponer de metodologías adecuadas para la caracterización de los alimentos, especialmente para determinar su contenido en componentes minoritarios bioactivos. Para contribuir a dar respuesta a esta necesidad actual, la tesis tiene por objetivo el desarrollo de metodologías que permitan la identificación, verificación, cuantificación y eficiencia de compuestos bioactivos, concretamente de los compuestos fenólicos. Estas metodologías serán herramientas de trabajo de gran utilidad para facilitar la formulación de nuevos alimentos con alegaciones de propiedades saludables.
El trabajo se ha centrado en la obtención y evaluación de compuestos fenólicos de dos fuentes de origen vegetal, el cacao y la algarroba. Los extractos de cacao son una fuente reconocida de compuestos fenólicos, principalmente de procianidinas, y alcaloides. La aceptación de los productos elaborados a partir del cacao es universal y durante los últimos años son numerosos los estudios que confirman que los fenoles presentes en el chocolate, procedentes del cacao, tienen efectos beneficiosos para la salud. Sin embargo, el alto contenido en grasas saturadas, así como la riqueza en azúcares son factores limitadores para el consumo de chocolate en el contexto de una dieta equilibrada. Por este motivo se propuso el estudio de una fuente alternativa, la harina de algarroba, al presentar un contenido bajo de grasa y ser una fuente rica de fibra. El estudio se dirige básicamente hacia la ampliación de las herramientas para la caracterización de la fracción fenólica, y para evaluar tanto la capacidad antioxidante como el efecto del procesamiento tecnológico sobre los compuestos fenólicos. Para alcanzar este último hito se trabajó con diversos productos derivados del procesamiento del cacao, concretamente el haba de cacao, el nib, el licor de cacao y el polvo de cacao.
Los resultados de este trabajo comprenden el desarrollo de técnicas cromatográficas que permiten identificar y cuantificar el perfil fenólico de los derivados del cacao y de la harina de algarroba (UPLC-MS/MS), así como técnicas espectrofotométricas que se presentan como herramientas rápidas de selección de extractos fenólicos (Folin-Ciocalteau y el ensayo de Vainillina). Al mismo tiempo, se ha optimizado dos metodologías de extracción que han permitido la obtención de extractos ricos en compuestos fenólicos a partir de ambas fuentes de estudio. Los extractos polifenólicos obtenidos han sido evaluados en términos de la capacidad antioxidante a nivel in-vitro aplicando el método DPPH y poniendo a punto y aplicando el método ORAC. Finalmente, se ha evaluado la estabilidad de los compuestos fenólicos de las matrices de estudio en medios que simulan las condiciones fisiológicas del proceso de digestión humana, para lo que se ha desarrollo de un modelo de digestión gastrointestinal in-vitro. Los resultados han mostrado un claro efecto de la composición de la matriz alimentaria sobre la estabilidad de los compuestos fenólicos durante el proceso de digestión. Estos resultados serán de gran utilidad en la formulación de nuevos alimentos con alegaciones de propiedades saludables.
Nowadays, there has been a growing interest in polyphenols because of their physiological health benefits, including antioxidant activity in the areas of nutrition, health and medicine. In parallel, there is increasing consumer demand for food information concerning nutritional needs as well as the improvement of health. All these concepts, together with the imminent definition of the European legislation in relation to the nutritional profiles and the allegations of health claims, involve the availability of suitable methodologies for food characterization. To respond to these requirements, this thesis is focused on the development of methodologies that allow the identification, verification and quantification of the bioactive compounds (polyphenols). These methodologies are presented as tools of work, which have to facilitate the formulation of new foods with alleged health benefits.
In order to reach these aims, this work selected two vegetable-origin sources to obtain and evaluate phenolic extracts: cocoa and carob. It is well-known that the polyphenol content of cocoa beans is mainly procyanidins, and alkaloids; however, this can vary greatly between different varieties and origins of the beans and also through the manufacturing processes. This work was focused on the evaluation of the cocoa bean and its by-products (nib, liquor and cocoa powder) as a potential source of bioactive compounds (polyphenols), which can be used as ingredients in the food and chocolate industry. The products elaborated from cocoa are universally accepted. In addition, different studies have shown recently that the consumption of cocoa and its products have positive and varied health effects. However, cocoa products contain high levels of saturated fatty acids and sugar, which limit the increase in their consumption in a balanced diet. For these reasons, carob flour was proposed as an alternative source with a marked nutritional value due to its high levels of dietary fiber and phenol compounds.
The results of this work are the development of several chromatographic techniques, which allow the phenolic profile of cocoa derivatives and carob flour (UPLC-MS/MS) to be defined and quantified. In addition, several spectrophotometrical techniques are proved as fast tools for monitoring the phenol yield efficiency of the obtained extracts (Folin-Ciocalteau and the Vainillin assay). Also, two optimized extraction methodologies have allowed phenol-rich extracts to be obtained from cocoa and carob. The phenol extracts obtained have been evaluated in terms of their antioxidant capacity using in-vitro methods, such as DPPH and ORAC. Finally, the stability of the phenolic compounds in cocoa and carob samples has been studied under human physiological digestion conditions through the development of an in-vitro gastrointestinal model.