Implications of nitrogen compounds during alcoholic fermentation from some grape varieties at different maturation stages and cultivation systems

The aim of this work was to study the influence of grape variety, cultivation system and stage of grape maturation on nitrogen compounds evolution during alcoholic fermentation. To do this, four grape varieties, Monastrell, Merlot, Syrah and Petit Verdot, traditionally cultivated and Monastrell cultivated using organic agriculture, which were collected in two different stages of maturation, were used. The results showed that, regardless of grape variety, cultivation system and stage of grape maturation, the consumption of nitrogen compounds was directly proportional (R-2 > 0.7) to their concentration in natural musts. This is very important as it is the first time that these results were obtained with natural musts without external addition of nitrogen compounds. (C) 2010 Elsevier Ltd. All rights reserved.