What is the effect on flavor profile if using first-fill American oak barrels that have been seasoned for 36 months as opposed to 12 months?

Using first-fill American oak barrels seasoned for 36 months as opposed to 12 months will significantly alter the flavor profile of the aged spirit. Seasoning refers to the process where oak staves are air-dried outdoors before barrel construction. Longer seasoning times result in a more mellow and nuanced flavor extraction during aging. A 36-month seasoning period will lead to a more subtle and integrated oak influence. The longer air-drying period reduces the concentration of harsh tannins and other undesirable compounds in the wood. These compounds, if extracted into the spirit, can contribute to bitterness and astringency. Longer seasoning also allows for microbial activity within the wood, which breaks down complex carbohydrates and other compounds, resulting in more desirable flavor precursors. A barrel seasoned for only 12 months will impart a more aggressive oak flavor. Expect stronger vanilla, caramel, and toasted notes, along with a higher concentration of tannins. Example: A spirit aged in a 12-month seasoned barrel might exhibit a more pronounced woody or spicy character initially. Spirits aged in 36-month seasoned barrels generally develop a smoother, more balanced flavor profile with a greater complexity arising from the breakdown of wood components into gentler flavor compounds. The spirit will likely have a softer mouthfeel and a more harmonious integration of oak-derived flavors. The longer seasoning period also reduces the risk of the spirit extracting harsh or bitter notes from the wood, resulting in a more refined and palatable final product. The distiller gains more control over the spirit’s final profile.