At DEEP CASK, we know oxygen is not just a bystander in whiskey aging. Instead, it is an active agent of change—one that shapes flavor, aroma, and complexity over time. However, traditional barrels offer no control over how much oxygen gets in. That is why we developed the AirBung—a new approach that applies the principles of gas diffusion. It allows distillers to actively manage oxygen, opening a new dimension in whiskey maturation.
From Passive Diffusion to Active Oxygen Management
The AirBung is a barrel bung with a built-in oxygen-permeable film. Rather than relying on the barrel’s slow, variable oxygen flow, distillers can now set a defined ingress rate. No guesswork. No surprises.
At the heart of the AirBung is an ultra-thin polymer film. This film acts like a selective gateway. It allows oxygen to pass through at a steady, predictable rate—while preventing ethanol or water from escaping. This enables the benefits of oxygenation without the cost of evaporation.
Science Guided Design
The underlying physics is well established. We apply Fick’s First Law of Diffusion and Henry’s Law to guide the design of the AirBung. By adjusting the film’s material, thickness, and surface area, we can precisely control how much oxygen enters the cask. In short, it’s a tunable interface for oxidative maturation.
AirBung offers something new: the potential for oxidative control. You can tailor how fast your whiskey breathes. You can align oxygen delivery with cask characteristics, mash bill, or maturation goals. And, you can standardize conditions across a warehouse.
The Promise
The promise? More flavor. More consistency. Less waste.
AirBung is more than just a tool—it’s a new mindset. A move from passive aging to informed, data-driven craft maturation. From waiting and hoping, to measuring and guiding. That is the promise of active oxygen management.
We believe whiskey deserves this level of attention. And we built the AirBung to make that future possible.