Contribution of phenolic compounds to the total antioxidant capacity of Pinotage wine

Grape ripening is a critical phenophase during which many metabolites driving wine quality are accumulated in berries. Major changes in berry composition include a rapid increase in sugar and a decrease in malic acid content and concentration. Its duration is highly variable depending on grapevine variety, climatic parameters, soil type and management practices.

Vineyards are highly variable and this variation is largely driven by environmental conditions and seasonal variation. For example, warm temperatures

Introduction and objective: the practice of physical exercises in an exhaustive way is related to damage. Muay thai (mt) is a high-intensity sport that demands agility, strength and power, which can lead to fatigue and muscle damage. Grape juice is rich in carbohydrates and antioxidants, which can delay the onset of fatigue and muscle damage. The objective of the study was to evaluate the impact of white grape juice consumption, during 14 days, on muscle damage parameters in tm athletes.

Knowledge on the reflectance spectrum of soil is potentially useful since it carries information on soil chemical composition that can be used to the planning of agricultural practices. If compared with analytical methods such as conventional chemical analysis, reflectance measurement provides non-destructive, economic, near real-time data. This paper reports results from reflectance measurements performed by spectroradiometry on soils from two vineyards in south Brazil. The vineyards are close to each other, are on different geological formations, but were subjected to the same management. The objective was to detect spectral differences between the two areas, correlating these differences to variations in their chemical composition, to assess the technique’s potential to predict soil attributes from reflectance data.To that end, soil samples were collected from ten selected vine parcels. Chemical analysis yield data on concentration of twenty-one soil attributes, and spectroradiometry was performed on samples. Chemical differences significant to a 95% confidence level between the two studied areas were found for six soil attributes, and the average reflectance spectra were separated by this same level along most of the observed spectral domain. Correlations between soil reflectance and concentrations of soil attributes were looked for, and for ten soil traits it was possible to define wavelength domains were reflectance and concentrations are correlated to confidence levels from 95% to 99%. Partial Least Squares Regression (PLSR) analyses were performed comparing measured and predicted concentrations, and for fifteen out of 21 soil traits we found Pearson correlation coefficients r > 0.8. These preliminary results, which have to be validated, suggest that variations of concentration in the investigated soil attributes induce differences in reflectance that can be detected by spectroradiometry. Applications of these observations include the assessment of the chemical content of soils by spectroradiometry as a fast, low-cost alternative to chemical analytical methods.

Le comportement de la vigne en terme de fonctionnement thermique et hydrique, influe de manière directe sur la qualité des baies de raisin. L’effet du terroir peut être perçu à travers l’étude de paramètres tels que la précocité, la mise en place de la surface foliaire ou la vigueur. Une expérimentation a été conduite en Val de Loire sur le cépage chenin dans le but de mieux comprendre le rôle des variables liées au terroir sur la croissance et le développement de la vigne et in fine sur la qualité des baies.