Gamificación y otras estrategias docentes en seminarios y prácticas de laboratorio de la asignatura Nutrición y Bromatología

Durante el curso 2018/2019 se ha realizado un ciclo de mejora en la asignatura Nutrición y Bromatología en la partes correspondientes a los seminarios y prácticas de laboratorio. La propuesta para este curso se ha centrado en la gamificación de los seminarios para conseguir por parte del alumnado un seguimiento más continuado de esta parte de la asignatura. En el caso de las sesiones de laboratorio, los alumnos han planteado dos preguntas a las que la práctica daba respuesta. Tras la realización de la práctica se volvió a pedir otra vez las preguntas y mediante un pequeño debate se decidió si la realización de dicha práctica había dado respuesta o no y con qué conceptos básicos estaban relacionadas las respuestas obtenidas en un mapa de contenidos. Tras dicha actividad se evaluaron los modelos mentales iniciales y finales de los estudiantes

On the Use of Adaptive Flipped Classroom in the Nutrition and Food Science Subject. Second Part

En el presente capitulo se describe el ciclo de mejora en el aula (CIMA) desarrollado en la asignatura Nutrición y Bromatología del Grado en Farmacia de la Universidad de Sevilla. En este CIMA se ha aplicado el uso del aula invertida adaptativa por segunda vez en la misma asignatura. El CIMA ha tenido una buena acogida entre los alumnos y los resultados obtenidos son satisfactorios. Además, durante el desarrollo de esta mejora docente se han identificado varias características a mejorar en la actividad docente desarrollada y que serán tenidas en cuenta en el futuro.This chapter describes the Improvement Cycles in Classroom (ICIC) in the Nutrition and Food Science subject (degree in Pharmacy of the Universidad de Sevilla). The adaptive flipped classroom methodology has been applied for a second consecutive time. This ICIC has been well-accepted among the students and the obtained results are satisfactory. In addition, several characteristics to be improved in the teaching activity have been identified and will be considered in the future

Estimation of Total Phenols, Flavanols and Extractability of Phenolic Compounds in Grape Seeds Using Vibrational Spectroscopy and Chemometric Tools

Near infrared hyperspectral data were collected for 200 Syrah and Tempranillo grape seed samples. Next, a sample selection was carried out and the phenolic content of these samples was determined. Then, quantitative (modified partial least square regressions) and qualitative (K-means and lineal discriminant analyses) chemometric tools were applied to obtain the best models for predicting the reference parameters. Quantitative models developed for the prediction of total phenolic and flavanolic contents have been successfully developed with standard errors of prediction (SEP) in external validation similar to those previously reported. For these parameters, SEPs were respectively, 11.23 mg g−1 of grape seed, expressed as gallic acid equivalents and 4.85 mg g−1 of grape seed, expressed as catechin equivalents. The application of these models to the whole sample set (selected and non-selected samples) has allowed knowing the distributions of total phenolic and flavanolic contents in this set. Moreover, a discriminant function has been calculated and applied to know the phenolic extractability level of the samples. On average, this discrimination function has allowed a 76.92% of samples correctly classified according their extractability level. In this way, the bases for the control of grape seeds phenolic state from their near infrared spectra have been stablished.España MINECO AGL2017-84793-C2España, Universidad de Sevilla VPPI-II.2, VPPI-II.

Valorization of American Barrel-Shoot Wastes: Effect of Post Fermentative Addition and Readdition on Phenolic Composition and Chromatic Quality of Syrah Red Wines

The influence of post fermentative addition of American barrel-shoot wastes on phenolic composition and chromatic quality of Syrah red wines has been evaluated as an environmentally sustainable alternative to the conventional winemaking for avoiding the common color loss of red wines elaborated in warm climates. American oak wood byproducts added were previously classified by hyperspectral image analysis according to the amount of phenolic compounds transferred to the extraction media. After that, wines were elaborated under different maceration conditions by applying only one proportion of wood (12 g L−1) and two different maceration procedures (simple and double addition) and were compared with a traditionally macerated Syrah red wine (CW, no wood addition). Results proved the effectiveness of the moderate postfermentative addition of oak wood byproducts to stabilize the color of wines and to provoke lower color modification along the time, producing color wines chromatically more stable for a better aging. In the case of double addition, the adsorption of the pigments during the maceration presents a stronger effect on the color than copigmentation and polymerization by cause of the copigments extracted from the woodEspaña, Ministerio de Economía y Competitividad AGL2017-84793-C

Multivariate analysis of sensory data of Vitis vinifera L. cv. Graciano during ripening. Correlation with the phenolic composition of the grape skins

The aim of this work was to evaluate sensory changes in grape skins during ripening and to obtain a correlation with their phenolic composition. Flavan-3-ols (monomers and dimers), prodelphinidins, hydroxybenzoic acids, hydroxycinnamic acids, anthocyanins and flavonols were determined by HPLC-DAD-MS. In addition, skin dilaceration, tannic intensity, astringency, acidity, aroma intensity (AI) and type of aroma were evaluated. Multivariate analysis showed the evolution of these samples during ripening and the relationship among sensory scores and phenolic composition of grapes skins. Skin dilaceration, type of aroma and to a lesser extent AI tend to increase during ripening. The contents in the phenolic compounds in grape skins present a similar pattern to the aforementioned sensory parameters. Nevertheless, tannic intensity, astringency, dryness and acidity present an opposite pattern which indicates a decrease of these sensory scores during ripening.Ministerio de Ciencia e Innovación AGL2008-05569-C02-01Consolider-Ingenio 2010 Programme CSD2007-0006

Comparative study on the use of anthocyanin profile, color image analysis and near-infrared hyperspectral imaging as tools to discriminate between four autochthonous red grape cultivars from la Rioja (Spain)

Three independent methodologies were investigated to achieve the differentiation of red grapes from different grape varieties (Garnacha, Graciano, Mazuelo and Tempranillo) collected from five vineyards located in the D.O.Ca. Rioja. Anthocyanin chromatographic analysis, color image analysis and near infrared hyperspectral imaging were carried out for the grapes. Then, a Stepwise Linear Discriminant Analysis (SLDA) was developed for each data set in order to discriminate grapes according to their grape variety. As a result, using anthocyanin profile, color image analysis and near infrared hyperspectral imaging respectively, 88%, 54% and 100% of the samples were correctly classified in the internal validation process and 86%, 52% and 86% were correctly classified in the leave-one-out cross-validation proces

Use of near infrared hyperspectral tools for the screening of extractable polyphenols in red grape skins

Hyperspectral images of intact grapes were recorded at harvest time using a near infrared hyperspectral imaging system (900–1700 nm). Spectral data have been correlated with red grape skin extractable poly- phenols (total phenolic, anthocyanins and flavanols) by modified partial least squares regression (MPLS) using a number of spectral pretreatments. The obtained results (coefficient of determination (RSQ) and standard error of prediction (SEP), respectively) for the developed models were: 0.82 and 0.92 mg g-1 of grape skin for extractable total phenolic content, 0.79 and 0.63 mg g-1 of grape skin for extractable anthocyanin content, 0.82 and 0.45 mg g-1 of grape skin for extractable flavanol content. The obtained results present a good potential for a fast and reasonably inexpensive screening of the extractable poly- phenolic compounds in intact grapes. Moreover, the heterogeneity of extractable polyphenols within the ripeness stage has been also evaluated using the proposed method

Study of phenolic extractability in grape seeds by means of ATR-FTIR and Raman spectroscopy

Near infrared hyperspectral imaging has been applied to grape seeds in order to select a representative subset of samples according to their spectral features in the 900-1700nm range. Afterwards, selected grape seeds have been classified according to their total phenol and flavanol extractabilities. In this way, samples were sorted in three different groups identified as low, medium and high extractability levels. In order to establish the chemical structures which can be responsible for the different extractabilities, vibrational spectroscopy has been applied to the non-extracted material after seed extractions. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) and Raman spectra of non-extracted seed material have been recorded and their main spectral features have been linked to extractabilities of flavanolic and total phenolic compounds. The vibrational spectroscopic analysis confirms that grape seed phenolic extractability is influenced by the cell wall composition (polysaccharides, lignins, pectins) and by the degree of esterification of pectins

On the use of vibrational spectroscopy and scanning electron microscopy to study phenolic extractability of cooperage byproducts in wine

Wood is an important source of phenolic compounds, which can be transferred to wine during aging process, improving its properties, from an organoleptic point of view. Therefore, understanding and optimizing the extractability of phenolic compounds from wood are crucial in the oenological field. The structural composition of oak wood samples has been evaluated using Raman and attenuated total reflectance Fourier transform infrared (ATR–FTIR) spectroscopies, and their main spectral features have been linked to phenolic compound extractabilities, as measured by classic chemical analyses. To support the analysis, microscopic images of the samples were also recorded using scanning electron microscopy (SEM). The applied methodology is shown to be useful to relate the wood cell wall structure to phenolic extractability levels of wood samples. It could assist in selecting oak wood suited for improving wine quality with regard to its color or/and stability through the addiction of external copigments to wine

Sensory evaluation of bitterness and astringency sub-qualities of wine phenolic compounds: synergistic effect and modulation by aromas

[EN] Mouthfeel characteristics of wine phenolic compounds (catechin, epicatechin, coumaric acid, caffeic acid, protocatechuic acid and gallic acid) were evaluated by sensory analysis using a Labeled Magnitude Scale for rating the intensity of the perceived sensations. Synergisms on bitterness and on astringent sub-qualities were detected when the phenolic compounds were tested as mixtures in comparison to individual compounds, maintaining the total amount of stimulus constant in all tasted samples. Principal component analysis was applied to observe trends in the data and to indicate relationships between phenolic substances and sensory attributes. It allowed us to easily visualize the synergistic effect discussed above. To our knowledge, this is the first time that astringency synergism between phenolic compounds has been described. This research also shows that wine aromas may modulate the perception of the astringency. In this study, the addition of volatile compounds increased the intensity of the astringent perception of the flavanol solutions and also its persistence