Identification of dialkylpyrazines off-flavors in oak wood
Langue
EN
Article de revue
Ce document a été publié dans
Journal of Agricultural and Food Chemistry. 2019, vol. 67, n° 36, p. 10137-10144
Résumé en anglais
Volatile extractive compounds from high-quality oak wood (Quercus sp.) are responsible for important pleasant olfactory notes, such as coconut, wood, vanilla, caramel, and spice. Recently, a new off-flavor reminiscent of ...Lire la suite >
Volatile extractive compounds from high-quality oak wood (Quercus sp.) are responsible for important pleasant olfactory notes, such as coconut, wood, vanilla, caramel, and spice. Recently, a new off-flavor reminiscent of rancid butter has been detected in oak wood. Using gas chromatography-olfactometry (GC-O) coupled to several detection modes, such as nitrogen-phosphorus detection (GC-O-NPD) or mass spectrometry (GC-O-MS) and multidimensional GC-O coupled to time-of-flight mass spectrometry, six compounds containing nitrogen atoms were identified. The volatiles were suggested to belong to 2,5-disubstituted pyrazines family, which was confirmed by comparison with synthetic reference compounds. For this purpose, symmetric and dissymmetric 2,5-dialkylpyrazines were prepared. from methyl esters of corresponding aliphatic amino acids (Val, Leu, and Ile) by a three-step, one-pot reaction under mild reducing conditions. Organoleptic descriptors and odor detection thresholds were also determined, whereas a bacterial origin explaining these off-flavors was hypothesized.< Réduire
Mots clés en anglais
Aroma
Barrel Aging
Dialkylpyrazine
Oak Wood
Off-Flavor
Wine
Unités de recherche