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Grenache (GN) and Cabernet Sauvignon (CS) are two traditional red grape varieties widely cultivated in the Mediterranean area and both late-ripening cultivars, which makes them less sensitive to global warming conditions and more stable to harvest timing. Although different studies have evaluated the final antioxidant properties of grapes and pomaces, few studies have explored the effect of sun exposure and harvest on the nutritional and antioxidant properties of these products. This study investigates the control of sunlight and ripening as tools to tailor nutritional and antioxidant properties of grape juices (GJ) and their byproducts (pomace GP). The compositional analysis showed no significant (p ≥ 0.05) differences associated to either harvesting timing or exposure to sunlight for either of the two studied varieties. However, differences (p ≤ 0.05) were observed between varieties of protein and total dietary fibre (TDF). CS protein content ranged from 0.52 to 3.88 (g 100 g−1) in GJ and from 1.0 to 1.32 (g 100 g−1) in GP; meanwhile, GN had higher protein values in GJ (from 2.11 to 4.77 g 100 g−1) and GP (from 5.11 to 6.75 g 100 g−1). The opposite behaviour was observed in TDF; CS grape had higher values for juice (from 11.43 to 19.53 g 100 g−1) and pomace (from 42.20 to 65.80 g 100 g−1) than GN (from 11.43 to 17.22 g 100 g−1 in juice and from 25.90 to 54.0 g 100 g−1 in pomace). The total phenolic content (TP) in GP was 100 times higher than in the juices and showed a much less pronounced evolution compared to the GJ during the harvesting time. GN TP values ranged from 5835 to 8772 mg GAE 100 g−1; meanwhile, CS values ranged from 7637 to 9040 mg GAE 100 g−1. A significant (p ≤ 0.05) correlation between the TP total antioxidant capacity (TAC) results was observed, regardless of variety, harvesting time, and sunlight exposure. These findings show how the control of different factors can contribute to obtain modified grape-derived products from conventional varieties beyond the wine market.

The variability in grape ripening is associated with the fact that each grape berry undergoes its own biochemical processes. Traditional viticulture manages this by averaging the physicochemical values of hundreds of grapes to make decisions. However, to obtain accurate results it is necessary to evaluate the different sources of variability, so exhaustive sampling is essential. In this article, the factors “grape maturity over time” and “position of the grape” (both in the grapevine and in the bunch/cluster) were considered and studied by analyzing the grapes with a portable ATR-FTIR instrument and evaluating the spectra obtained with ANOVA–simultaneous component analysis (ASCA). Ripeness over time was the main factor affecting the characteristics of the grapes. Position in the vine and in the bunch (in that order) were also significantly important, and their effect on the grapes evolves over time. In addition, it was also possible to predict basic oenological parameters (TSS and pH with errors of 0.3 °Brix and 0.7, respectively). Finally, a quality control chart was built based on the spectra obtained in the optimal state of ripening, which could be used to decide which grapes are suitable for harvest.

Spatially offset Raman spectroscopy (SORS) is a non-invasive analytical technique that allows the analysis of samples through a container. This makes it an effective tool for studying food and beverage products, as it can measure the sample without being affected by the packaging or the container. In this study, a portable SORS equipment was used for the first time to analyse the alcoholic fermentation process of white wine. Different sample measurement arrangements were tested in order to determine the most effective method for monitoring the fermentation process and predicting key oenological parameters. The best results were obtained when the sample was directly measured through the glass container in which the fermentation was occurring. This allowed for the accurate monitoring of the process and the prediction of density and pH with a root mean square error of cross-validation (RMSECV) of 0.0029 g·L−1 and 0.04, respectively, and R2 values of 0.993 and 0.961 for density and pH, respectively. Additionally, the sources of variability depending on the measurement arrangements were studied using ANOVA-Simultaneous Component Analysis (ASCA).

The content of biogenic amines in wines and other fermented beverages has been extensively studied over the last 25 years because of the physiological effects which their consumption might lead to, in particular in the presence of alcohol. From the health point of view, this may indicate that the hygienic conditions while the beverage in question was being produced were deficient. Thanks to the rapid evolution of analytical techniques, there is now a better knowledge of the origin and the content of biogenic amines in wines. At present, data about concentrations are suufficiently reliable for rules to be established about the maximum recommendable limits in each country, although as yet there are no legal, unified regulations. The most widely used analytical methods for determining biogenic amines nowadays are based on chromatographic separation procedures and, in particular, on High Performance Liquid Chromatography (HPLC). This study reviews research which has compiled data about the presence of biogenic amines in wines and about the analytical techniques used to determine them, putting special emphasis on HPLC methods and the sampling treatments necessary to carry out the analyses.

En el presente trabajo se hace un análisis y discusión desde la perspectiva de género de los cambios en cuanto a la inserción acelerada de las mujeres en la educación superior en México, a partir de la década de los setenta. Mientras que en 1969 las mujeres en México representaban sólo la quinta parte (17 %) en este nivel educativo, desde el año 2000 se llegó al 50 % (en 30 años se triplicó). Más aún, se ha observado una recomposición de los porcentajes de mujeres y hombres en ciertas áreas del conocimiento, como Ciencias de la Salud y Ciencias Sociales y Administrativas, que hasta iniciada la década de los ochenta, los porcentajes más altos correspondían a hombres, en tanto que en la actualidad las mujeres ocupan el 61 y 57 % respectivamente. Sin embargo, como ocurre en muchos otros países, también en México el campo de las ingenierías registra los porcentajes más bajos de mujeres, representando apenas la cuarta parte de la matrícula total, a pesar de que en los últimos 20 años las mujeres han triplicado su inserción en esta área del conocimiento. La discusión se hace desde un enfoque de género, en términos de las implicaciones sociales, familiares y económicas para las mujeres con una profesión que tratan de insertarse al mercado laboral, así como los obstáculos a los que se enfrentan. Se plantea la necesidad urgente de seguir trabajando en políticas públicas orientadas a la equidad de género.