Why a Kiss of French Oak is the Perfect Finish for American Rye

French oak barrels have been a revelation for more than two millennia, since the Romans conquered the Gauls and immediately adopted this exciting new technology throughout the Empire. They ditched the wax-lined clay amphorae they had been using to transport wine, olive oil and other precious liquids, because they were harder to seal and more breakable than the comparatively lightweight, rollable barrels.

Beyond transporting liquid safely, today’s wine and whiskey makers are far more focused on the flavors imparted by the barrels into the liquid within. These influences can vary with barrel shape, wood species, the age and curing of the staves, the interior toast and char levels, and in some cases, what wine or spirit it previously contained.

Each of these considerations came into play when Heaven’s Door Head of Whiskey Development Ryan Perry trialed hundreds of different barrel finishes and ultimately selected cigar-shaped barrels of new, exclusively air dried French oak from the forests of Vosges.

“Straight Rye is a naturally spicier whiskey,” Perry said, “and the French oak is a great complement to that. It is tighter grained and less dense, resulting in more subtle, silkier flavors than American oak.”

Our rye first spends six years in American oak before finishing for about a year in French oak, soaking up the best of both woods. American oak is considered more “in your face,” tannic, strongly imparting flavors like vanilla and cream soda. French oak is often described as having softer tannins and making more subtle, spicy and complex flavor contributions.

To understand why this is so and why, 2,000 years on, oak still dominates the barrel world, it’s helpful to understand a bit of tree anatomy, starting with a factor that has a tremendous impact on flavor: grain. Wood’s grain is said to be either “tight” or “loose” based on how close a tree’s annual growth rings are to one another.

Tightness of grain has a huge impact on flavor. It’s somewhat counterintuitive, but the tighter the grain, the more porous the wood (the reason is complex and to explain why we’d have to get deep into tree anatomy, which we will another time). Throughout much of its range, American oaks tend to have a longer growing season and are looser-grained as a result, whereas French oaks tend to have shorter growing seasons and a tighter grain, and consequently can impart flavor more quickly due to greater porousness.

The wood for our Straight Rye Whiskey comes from Vosges, one of six primary forests where French oak has been harvested since the shipbuilding Napoleonic era. (The others are Allier, Bertranges, Limousin, Nevers and Tronçais.) French oak staves are hand split and air dried for three years in the elements, a lengthy process but one which preserves and develops new flavor compounds. Kiln drying, on the other hand, which is traditional to almost all American oak, is faster but far less gentle on flavor-producing compounds.

Our cooper fashions our Vosges staves into cigar-shaped barrels, which gives us more ‘whiskey-on-wood’ contact than a traditionally shaped barrel for faster flavor infusion. As noted before, French oak is porous, and during aging our whiskey soaks as deep as 6mm into the staves, increasing the ‘angel’s share’ drunk by the wood.

“A French oak cigar barrel will soak up more than ten gallons of whiskey over forty-five days,” Perry said. “We lose about 15-20 percent of our whiskey in order to achieve our uniquely smooth finish.”

The elongated cigar barrel shape increases the length of the staves and their joints, which is the site where much of the oxidation of the whiskey takes place, along with where the staves join the barrel head. Instead of charring the interior of our barrels, we gently toast our barrels to heighten vanilla and spice notes. The reason for this is that these are finishing barrels designed to impart more flavor and complexity, and charring the barrel creates charcoal which would filter some of those flavors out.

We agree with what noted whiskey expert F. Paul Pacult wrote about our results:

“A rye that does appreciably and with confidence show the bright, tangy, tropical fruit side of the grain that produced colonial America’s first successful whiskey.”

Tasting Notes Heaven’s DOor
Straight Rye Whiskey

Our proprietary barrel finishing results in a smoother, more approachable rye, with notes of orange peel, coriander and spice.

Tim Toomey

President of COVERT NINE, a digital marketing and design company based in Chicago, Illinois.