Varietal flavour compounds of four grape varieties producing Madeira wines

• Autor(a) principal: Câmara, J. S.
• Data de Publicação: 2004
• Outros Autores: Herbert, Paulo, Marques, J. C., Alves, Maria Arminda
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.13/913
• topic: Boal variety; Malvasia variety; Sercial variety; Verdelho variety; Must; Free terpenoid compounds; Headspace solid-phase microextraction; Gas chromatography-mass spectrometry; Principal component analysis; Linear discriminant analysis; .; Faculdade de Ciências Exatas e da Engenharia

Boal, Malvasia, Sercial and Verdelho are the main white grape varieties used in Madeira wine production. To estimate the free fraction of varietal aroma compounds of these varieties, 39 samples of musts were analysed to determine their content of monoterpenols and C13 norisoprenoids (terpenoids), using dynamic headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry. The r-values for linearity studies of the analytical method used, varied between 0.977 (nerolidol) and 0.999 (linalool). The repeatability for each compound varied between 2.5% (citronellol) and 11.8% (β-ionone). The mean values from three vintages (1998, 1999 and 2000) confirmed that these musts have differentiated contents of terpenoids. In opposition to Verdelho musts, Malvasia showed the highest free terpenoids content. In order to establish relations between the compounds and the varieties under investigation, principal component analysis and linear discriminant analysis were applied to the data, revealing a good separation and classification power between the four groups as a function of varietal origin.