Contents of 3-alkyl-2-methoxypyrazines in musts and wines from\+i\ Vitis vinifera\-i\ variety Cabernet Sauvignon: influence of irrigation and plantation density

The influence of irrigation and plantation density on the methoxypyrazine content in musts and wines has been studied. Samples were monitored throughout grape ripening and wine-making. 3-Isobutyl-2-methoxypyrazine, 3-sec-butyl-2-methoxypyrazine and 3-isopropyl-2-methoxypyrazine were identified and quantified. Samples from irrigated vines had significantly higher average contents of 3-isobutyl-2-methoxypyrazine than samples from non-irrigated plants. Average levels of this compound were also higher in samples from vines with the higher plantation density.