Identification\nof Two New Taste-Active Compounds in\nOak Wood: Structural Elucidation of Potential β‑Methyl-γ-octalactone\nPrecursors and Quantification in Spirits

Barrel aging is a crucial stage that influences the taste\nof wines\nand spirits, particularly increasing their sweetness and bitterness.\nThis increase is caused by nonvolatile compounds released from oak\nwood. To search for such molecules, we performed a taste-guided inductive\nfractionation protocol using several analytical techniques. By using\nHRMS and NMR, two new galloylated derivatives were elucidated. Their\nenzymatic hydrolysis revealed the formation of β-methyl-γ-octalactone,\nindicating that they are potential precursors. The taste properties\nof these isomers revealed a sweet and bitter taste for P-WL-1 and\nP-WL-2, respectively. An LC-HRMS quantification method was performed\nto evaluate the influence of aging parameters such as botanical origin\nand toasting process on their concentrations. Several spirits were\nalso analyzed to confirm their presence in this matrix. These results\nimprove the understanding of the molecular markers responsible for\nthe taste of beverages.