Louisville KY | Paso Sherpa

Paso Sherpa First Impressions - Louisville, KY

Coming to Louisville, the first thing you might get is the impression that it’s just another Southern mid-sized city. But it’s poised for growth, and all over town you see signs of new construction, expanding tourism, and — of course — the booming bourbon business.

We started our visit staying at a hotel just off 2nd and Main Streets, right in the heart of the old distillery district. You can walk up Main Street, stop into a fine restaurant that might also happen to be a distillery, and everywhere you go there are bourbon flights being served. And not just your standard 80-proof bourbon — this stuff is often cask strength, 105 to 110 proof, enough to turn your mouth into a flamethrower. But add a drop of water and suddenly it becomes liquid love.

My wife and I discovered that we’re probably more wine lovers than bourbon drinkers, but we absolutely fell in love with the juxtaposition between how bourbon is made versus how wine is made — especially when it comes to the barrels.

After milling around downtown for a couple of days, we finally headed to ISC, the International Stave Company, one of the largest barrel producers in the world. They claim to produce more than 90% of the barrels used in the bourbon industry, and after seeing their operation, I believe it. ISC produces somewhere between 750,000 and 1 million barrels annually. The facility uses a tremendous amount of proprietary technology — so much so that photography and video were strictly prohibited inside the factory. You’re just going to have to take my word for it: the scale is staggering. In 2024, Kentucky distillers filled more than 3 million barrels of bourbon, and even in a slower year like 2026, production remains massive.

Now let’s talk a little more about wine — because that’s really why we’re here.

I found it fascinating to watch the differences between whiskey barrels and wine barrels being produced. I had no idea just how different they really are. The barrel sizes differ, the woods differ, and even the production methods are unique.

For whiskey barrels, production starts primarily with American oak harvested from more than a dozen states. The oak trees generally need to be over 100 years old, but not too much older. After about a century, oak trees begin hollowing out internally, weakening the wood and reducing its quality for barrel production.

One interesting exception is California, where oak trees cannot legally be harvested solely for barrel production. However, if a tree naturally falls or fails, the wood may still be used. Bardstown Bourbon Company has even taken advantage of this by producing a California oak-aged bourbon.

For bourbon production:

Barrels must always be made from NEW oak.
The barrels are CHARRED, not toasted.
There are four standard char levels, from #1 through #4.
This “alligator char” helps create flavors of vanilla, caramel, smoke, and color.
Bourbon actually starts out as a clear spirit — essentially moonshine — and without oak, you cannot legally make bourbon.
Standard bourbon barrels are typically 53 gallons, or roughly 200 liters.

Wine barrels, on the other hand, are a completely different story.

Wine oak primarily comes from France and tends to be less porous, creating softer spice characteristics compared to the bolder flavors of American oak. Wine barrels are TOASTED rather than charred, and they are often reused anywhere from 3 to 10 times. By the third use, many barrels are considered “neutral,” meaning they no longer impart significant flavor or color into the wine. Wine barrels are also slightly larger, generally around 225–228 liters, or about 59 gallons. A high-end French oak barrel can cost anywhere from $1,200 to well over $2,500 each. Aging is critical to improving both bourbon and wine — but the two age in almost opposite ways. Once placed into barrels, bourbon typically ages for a minimum of 4–8 years, while premium bottles may age anywhere from 10 to 20 years or more. Unlike wine, however, bourbon stops aging once it enters the bottle. Wine continues to evolve and age after bottling.

Red wines may spend anywhere from several months to 2–3 years in barrel, while whites and lighter reds generally spend far less time in oak. Bourbon is traditionally stored in large open buildings called “rickhouses.” These towering warehouses, often 4–9 stories tall, can hold anywhere from 15,000 to 60,000 barrels. Historically built from wood — though now sometimes incorporating steel and concrete — these structures are intentionally exposed to dramatic seasonal swings in temperature and humidity.

Nature does the work. As temperatures rise, the bourbon expands into the charred oak. As temperatures cool, it contracts back out. This constant expansion and contraction deepens the interaction between the spirit and the barrel, accelerating flavor development.

Wine storage is almost the exact opposite.

Wine is typically aged in temperature-controlled caves or cellars, ideally maintained around 55 degrees Fahrenheit. Stability is everything. The goal is not aggressive extraction, but slow, controlled maturation.

Humidity also matters enormously, generally remaining between 60% and 70%. Proper humidity keeps corks from drying out and shrinking. If too much oxygen enters the bottle, the wine oxidizes prematurely and spoils.

With bourbon, longer aging generally creates smoother, sweeter, richer flavors.

With wine, the long-term magic often happens less in the barrel and more in the bottle. The barrel may contribute flavor early on, but true wine aging continues long after bottling, evolving slowly over time.

As a wine lover, I can say that a trip to the bourbon distilleries of Kentucky may not be your ultimate vacation, however, the education and history is fascinating and a great way learn just how different these worlds are.

Here are some fun facts: