How wood-scanning tech is taking the guesswork out of aging bourbon

OakScan analysis allows Penelope Bourbon to predict results with French Oak.

Photo by Billy Steele/Engadget

“It all came about at 11:30PM on a random Wednesday.”

Penelope Bourbon CEO and founder Michael Paladini admitted that late-night calls are a regular occurrence for him. After his wife goes to bed, the kids are asleep and there are no emails hitting his inbox, he has time to get creative. One of these evening brainstorming sessions was with Robert Crandell, a regional sales manager for Tonnellerie Radoux and Pronektar. Radoux is a French cooperage that has been making barrels for decades. The company has been operating in the US since 1994, based in wine country California. What’s more, Radoux has conducted extensive research into the chemical composition and tannins of French oak.

Since 2008, Radoux has completed over 300 trials containing over 10 million analyses to observe polyphenols in the wood that can impact the appearance, taste and smell of wine. The result is a tool that can instantly measure these properties with Near Infrared Spectrometry, rather than using the time-consuming process of taking random samples from various batches of staves. The technology is called OakScan.

Tonnellerie Radoux

“French oak can be wildly inconsistent,” Crandell noted.

All of the variation in French oak can lead to unintended results without careful planning. Combine that in with the fact that the wood is more expensive than American oak and companies using it to age wines and spirits can greatly benefit from knowing how their liquid is going to react to the wood. It’s long been known that trees from different forests that are made into barrels will have different chemical compositions (the concept of terroir), and thus different levels of tannins. There can also be significant variation in trees just a few feet apart or from staves made from different parts of the same tree. What’s more, there can be distinctions in the grain width, which affects the extraction time for getting the tannins out of the wood.

“Even if you’ve gone to great lengths and you bought wood from the same forest, you still aren’t getting the same sort of precision and consistency [as with OakScan],” Crandell said. When Radoux uses OakScan to analyze staves bound for production, each piece of wood is assigned a barcode and a letter corresponding to its “tannic potential,” according to the cooperage. This not only helps with sorting, but it allows the company to build barrels with a specific polyphenolic index (PI), ensuring the wood is suitable for the style a winery or vineyard is trying to make. And since every stave is scanned, there’s uniformity of the tannin content of each barrel and all the data makes the end result repeatable.

OakScan also allows customers to select wood from different forests, but not by sourcing actual staves from those places. Instead, Radoux can build the tannin profile and replicate the terroir in a much more consistent way.

“If someone wanted a Voges-style barrel, we could work that out based on tannin level,” said Radoux national sales manager Craig Holme. “We can be more precise on what [the results are] going to be. Someone else will get a barrel that may be from two different trees [in that forest], and they might be completely different.” According to Holme, Radoux can pull 1,000% extracts from the staves that they can then put in a sample of a prospective customer’s product to show them what it’s going to do.

Originally developed exclusively for wine making, OakScan was initially used to analyze the chemical characteristics of barrel staves. Once the system was developed and fine-tuned, Radoux began using the same technology for tank staves. Thinner than a barrel stave, these pieces of wood allow for a quicker extraction process, which at the time was intended for larger volumes of wine. Where barrels are only toasted on the inside, tank staves are finished on all six surfaces and they’re designed to be completely submerged.

“Typically, the toasting process for wine is much more precise than the charring process for spirits,” Crandell explained. “So we came up with something very precise and very repeatable.” However, OakScan hadn’t really been used extensively in the spirits industry, he continued, except for a “small, experimental project” he had done a few years ago. Eventually, Crandell said he started working with Penelope and another micro-distiller to see if the detailed analysis of French oak could work for spirits.

Penelope Architect
Penelope Bourbon

Penelope isn’t your traditional bourbon maker. The company doesn’t actually distill anything. Instead, it sources aged bourbon from MGP: a producer of distilled spirits with operations in ​​Kansas, Missouri, Indiana, Kentucky, and Ohio, in addition to Mexico and Northern Ireland. MGP has its own brands of spirits (it actually announced the acquisition of Penelope earlier this week), but it also sells bourbon, rye whiskey, gin and more to other companies to package and sell on their own. Penelope buys bourbon of various ages and mashbills from MGP and blends it to their specifications. Sometimes they’ll bottle those blends as-in (Four Grain Bourbon and Barrel Strength Bourbon), while others undergo additional aging before they’re packaged.

While Radoux primarily caters to vineyards in France, Italy, Spain, the US and more, its colleagues at Speyside Cooperage (both owned by TFF Group) typically work with breweries and distilleries. Paladini and Penelope COO and founder Daniel Polise initially worked with Crandell to secure Rosé casks for secondary aging of its bourbon. They then collaborated with Speyside Cooperage to source toasted American oak barrels for a secondary finishing of its bourbon. For that treatment, Penelope would create a blend of aged bourbon and put it in barrels with varying char and toast levels for a period of time. In the end, Paladini and Polise discovered that even with the same bourbon in the same barrels, samples from each would be very different.

“It would go in completely different, wild directions,” Paladini observed. “We found that to be great, and that’s why that product was incredible.” Indeed, Penelope Toasted Series Bourbon won gold at the San Francisco World Spirits Competition in 2022. The company leaned into the variation in the aging results, indicating the char and toast levels on the bottles of each batch. Of course, that means each batch is quite different.

Following the challenges of the Toasted Series, Polise tried using some of the OakScan staves in some samples. “We have so many different products that show up and people want us to try and use them,” he admitted. “I finally tried it and I was just shocked.” Polise explained that the OakScan French oak “stood out from the others greatly.”

Thus the idea for Penelope’s Architect Bourbon was hatched. The company was hoping to tap into the success of Toasted Series by once again being transparent about the types of wood they were using for secondary aging. But while OakScan can create the ultimate consistency batch to batch, Paladini says he and Polise weren’t sure they really wanted that.

Penelope OakScan
Photo by Billy Steele/Engadget

“Our first thought was to take an exploratory approach and highlight the actual flavor profile on the back of the label. That profile is coming directly from the oak engineer in France when they run the OakScan process,” said Paladini. On each bottle of Architect, there’s a spider graph that illustrates the characteristics of that particular “build.” The company is playing up the idea of constructing a flavor profile, so it calls each batch a “build” instead. Hence the name Architect.

With Architect, Penelope has created six different “builds” or stave selections and they’re all different. However, they’re still consistent, as Crandell explained. “We can make a build again, it’s repeatable,” he noted. And that’s because OakScan allows for that consistency rather than the company hoping they can recreate a hit. They will, of course, need to replicate the blended bourbon from MGP that undergoes the secondary aging in order to do so. Even if they can’t, the company can still give a new blend the same “build” as a previous version of Architect. Since the wood analysis gives them so much control over the end result, the combinations – and the creative potential – are seemingly endless.

“[OakScan] not only gives you the ability to be precise, but it also gives you the ability to be creative,” Crandell said. “If you know what the end result is going to be, you can change the end result – you can control the end result.”

For Penelope, French oak that’s been analyzed with OakScan is only being used in Architect right now. But, Paladini and Polise aren’t ruling out using the staves for another product in the future.

“We’re constantly playing with different woods and finishes,” Polise noted. “So whatever matches next, we may release. It just works like that.”