Aroma Potential in Early- and Late-Maturity Pinot noir Grapes Evaluated by Aroma Extract Dilution Analysis

Aroma potentials in early and late maturity Pinot noir grapes were investigated in two consecutive vintages. The grape samples were hydrolyzed under acidic conditions, and the released odorants were studied by aroma extract dilution analysis (AEDA). Forty-nine main odor-active compounds were detected in the AEDA. The odorants released with high flavor dilution values were 1-hexanal, β-damascenone, guaiacol, and vanillin, together with C6-aldehydes and -alcohols, 4-vinylguaiacol, 4-vinylphenol, and 1-octen-3-one. The concentrations of aroma-active compounds were further quantitated. Compared with early harvest grapes, late harvest grapes released more β-damascenone, vanillin, 4-vinylguaiacol, and 4-vinylphenol in both years according to both AEDA and quantitation results, suggesting they were important aroma compounds that contribute to the characteristic of matured Pinot noir grapes.