Influence of the year and the environmental factors on condensed tannins from Cabernet franc grapes

The chemical behavior of anthocyanins is considerably affected even by slight pH variations with impor-tant implications for the winemaking as well as for the wine conservation

Today winegrowers involved in mechanical winter pruning are applying this viticultural technique on two main training systems, the free cordon, appearing to be the more efficient, and the trellised vertical shoot positioning (VSP) system. The main reasons for maintaining the trellis are generally due to common habits in vineyard management, risk of wind damage for the shoots, or risk of decrease in photosynthesis potential. The aim of the study was to assess the effects of the two training systems on vine. In addition, different nitrogen fertilization levels were applied on the two systems to evaluate the best combination to achieve yield and grape quality.

Measuring the effect of oxygen consumption on the colour of wines as the level of dissolved oxygen decreases over time is very useful to know how much oxygen a wine is able to consume without significantly altering its colour. The changes produced in wine after being exposed to high oxygen concen-trations have been studied by different authors, but in all cases the wine has been analysed once the oxygen consumption process has been completed. This work presents the results obtained with the use of an equipment designed and made to measure simultaneously the level of dissolved oxygen and the spectrum of the wine, during the oxygen consumption process from saturation levels with air to very low levels, which indicate the total consumption of the dosed oxygen.

The zoning of grapevine in a hilly area should consider the variability of the environmental characteristics due to topography. Since soil and climate data are usually available as point data

PPhloem transport of assimilates provides the materials needed for the growth and development of reproductive structures, storage and developing organs, and has long been recognized as a major determinant in crop yield.