Wine Lees as a Source of Antioxidant Compounds

The winemaking industry produces large amount of byproducts, including grape pomace, stalks, and lees. Wine lees are a natural source of phenolic compounds, which have important antioxidant and biological properties. Due to the high quantities produced worldwide, this byproduct can be an ideal raw material for obtaining phenolic compounds that could be of interest in the food and pharmaceutical industries. In this mini review, the main characteristics of wine lees as well as their phenolic composition and antioxidant activity have been summarized from the information in the literatur

The Use of Grape Seed Byproducts Rich in Flavonoids to Improve the Antioxidant Potential of Red Wines

The influence of adding seeds from grape pomace during Syrah wine fermentation in a warm climate has been studied. Seeds of Pedro Ximenez variety were rich in phenolic compounds, mainly flavonoids such as catechin and procyanidins. Changes in total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity of red wines were observed. These changes depended on the vinification stage and the amount of seeds (SW: 450 g or DW: 900 g seeds/150 kg grapes) applied. In general, antioxidant activity was greater when a simple dose (SW) was considered. Results indicate that seeds rich in flavonoids could be used as wine additives, which could improve the antioxidant potential of red wines in a warm climate.Ministerio de Economía y Competitividad AGL2014-58486-C2-2-

Applications of Voltammetric Analysis to Wine Products

Wine contains polyphenols that are responsible for its quality. Moreover, phenolic compounds have antioxidant properties and benefits on human health. Cyclic voltammetry (CV) was the first electrochemical method used for polyphenols characterization and determination of polyphenols content in wine products. Electrochemical behaviour of standard solutions of phenolic compounds has been investigated and evaluated the importance of the phenolic concentration and pH. The electrochemical parameters extracted from the voltammograms have been correlated with the antioxidant potential in wine products. In addition, CV allowed establishing differences in the antioxidant activity of wines with different addition of grape seeds. In winemaking by-products, different Ipa and Q500 values were found depending on the state of maturation of the grape pomace. On the other hand, the total flavonoids and phenolic acids contents were significantly correlated to the electrochemical parameters. Differences for the electrochemical parameters were found between by-products, being pomace and seeds which presented the greatest values of Q500. Simple regression analyses showed that voltammetric parameters are correlated to their values of lipid peroxidation inhibition by thiobarbituric acid reactive substances method. Our results open the possibility of CV as a promising technique to estimate the global antioxidant potential of wine products rich in phenolic compounds

Determination of phenolic substances of seeds, skins and stems from white grape marc by near-infrared hyperspectral imaging

Background and Aims:Winemaking generates a large quantity of grape marc that causes environmental and economic problems, which could be minimised by exploiting and adding value to these by-products. Marc is composed of seeds, skins and stems that are an important source of phenolic substances, which have antioxidant properties and potential benefits to human health. It is necessary to develop novel methods for assessing the composition of marc because conventional analyses are destructive and require lengthy preparation procedures and chemical reagents. Methods and Results: Near-infrared hyperspectral imaging has been used for evaluating 27 individual phenolic substances in the components of grape marc after freeze-drying, the only sample preparation step. By applying partial least squares regression to the spectral data, values of R2 up to 0.98 were obtained even for estimating some minor compounds. Conclusions: This methodology arises as an attractive alternative to analyse the phenolic composition of grape marc because of its speed and simplicity. Significance of the Study: The use of this technique will allow wine producers to quickly determine the phenolic composition and decide the destination of this by-produc

Investigación en color y calidad de alimentos

En esta ponencia se pretende presentar a los alumnos de la Escuela Politécnica Superior, las líneas de investigación del grupo Color y Calidad de Alimentos de la Universidad de Sevilla (AGR225, PAIDI) y las posibilidades de realizar Trabajos postdoctorales o continuar las salidas profesionales en el campo de industrias alimentarias.This paper tries to introduce to the student of Polytechnic School, the research lines of Color and Food Quality Group of the University of Seville (AGR225, PAIDI), and the possibilities of carrying out postdoctoral works or continuing the career in the field of food industries

Implicaciones cromáticas del nivel de oxidación en vinos embotellados: efecto del tipo de corcho y la posición de la botella

Se estudió la evolución del color de un vino tinto joven durante su almacenamiento en botella, y la influencia de las características del tapón. Para ello se ensayaron cuatro tipos de corcho y se siguió la evolución de los parámetros cromáticos del vino en función de la posición de la botella. Los parámetros de color sufren mayores modificaciones cuando la botella se almacena en posición vertical, siendo la magnitud de éstas dependiente del tipo de corcho usado. Desde el punto de vista cromático, es preferible el uso del corcho natural o tecnológico ya que con ellos se consigue una menor modificación del color durante el proceso de almacenamiento, independientemente de la posición de la botella. Por el contrario, cuando se usa corcho aglomerado, la diferencia de color, para un mismo vino almacenado de pie o tumbado, puede llegar a ser incluso visualmente apreciable (∆E*ab ~ 6 unidades CIELAB)

Chemical composition and “ in vitro ” anti-inflammatory activity of Vitis vinifera L. (var. Sangiovese) tendrils extract

Grapevine ( Vitis vinifera L.) is currently used for wine production, herbal medicine and food supplements. In this study we investigated the phenolic composition of grape tendril extract (TVV), because these compounds are prob ably r esponsible for the observed biological effects of TVV. We performed our investigation on cells implicated in the inflammatory process and in vascular damage, such as monocyte (U937) and senescent endothelial (HUVEC) cells. We analysed changes in microRNA (miRNA) expression during a pro-inflammatory condition in LPS (lipopolysaccharide) stimulated cells. MiR-126, defined as angiomiR for its ability in the maintenance of endothelial cell functions, and miR-146a, defined as inflamma-miR, for its ability to down-modulate (NF-kB nuclear factor-kB) pro-inflammatory pathway, were analysed along with their targets.TVV extract (40 g/mL) was able to prevent the LPS stimu- lus and may play an important role in the prevention of endothelial dysfunction when the accumulation of senescent endothelial cells occurs