DIY & Inspo

Can I varnish my small oak liter aging barrel?

Midwest Barrel Co.

Small liter oak aging barrel on a stand A small oak aging liter barrel on a stand.

It’s a question we answer more often than you think: What will happen if I varnish my small oak liter aging barrel before filling it with whiskey or another type of spirit to age?

The answer to that question varies based on where you might look online – and from where you buy. Some folks tell you varnishing the barrel will interfere with the aging or even affect the taste of what you are maturing inside the small barrel. Others promise there won’t be any noticeable difference to how the barrel interacts with the spirit or cocktail you are aging and the liquid itself will be absolutely fine.

To tell you the truth? It depends…

'To be honest, the correct answer is somewhere in the middle. No, varnishing a small oak aging barrel will not alter its contents in a negative way. As long as you use a food-safe varnish or other coating – and let it dry before filling – then the varnish won’t pose any toxic health hazards Plus, you will still get some of the aging and oak flavor additions.

And just so you’re aware, the small oak aging barrels that we sell here at Midwest Barrel Co. have a light, clear coat of breathable polyurethane to spruce them up a bit.

However, adding a layer of varnish to the wood could seal the liter barrel and reduce the amount of air flow in and out. This is what starts up the aging process and kicks off a whole host of interactions between the liquid inside the barrel and the charred wood it is made out of.

If you’d like a deeper explanation, then continue reading. If you believe the straight-to-the-point, TL;DR version did the trick, then there’s no need. Age away varnished or unvarnished! Just don’t forget to take care of the new small barrel the correct way!

Varnished or unvarnished?

Brush with varnish from a can

At the end of the day, whether you varnish your small oak barrel is up to you. There is no harm in not adding varnish, but a few factors may determine whether you do or do not apply anything.

One way to decide whether you want to add a protective or decorative coating is to consider how the barrel is going to be used or where it is going to be displayed.

Reasons to varnish your barrel

Why might you elect to add a layer or two of varnish to a small barrel? Well, to be fair, they do look pretty sharp on display with a shiny or even clean matte finish.

Engraved barrels and custom barrel furniture look especially sharp on display after they’ve been finished up a bit. In fact, we usually spray a more breathable polyurethane on wine barrel heads to add some shine. We’ll do that upon request for any engraved product.

Additionally, customers have been known to varnish these products themselves after receiving them. You could easily do the same for a smaller barrel.

Any added coat will not only help spruce up the oak barrel, but it will also help it retain its color and maintain its overall appearance longer. Unvarnished barrels may tend to show a few more minor signs of weathering over time, although this would be an extended amount of time unless it is stored outside or directly in sunlight.

And don’t forget – you will still get plenty of added flavors to whatever you put inside the barrel. If you’re looking for a more realistic aging experience that would match what a distillery or winery might expect to get out of a new oak barrel, then we would recommend you keep reading.

Reasons not to varnish your barrel

As for reasons why you would choose not to varnish your barrel, there are plenty of those, too. But again, there are certain trade offs to consider.

First, many folks enjoy how barrels look when left alone. The natural oak coloring is beautiful and always varies, so you know that yours is unique in appearance. It’s worth asking why you would want to cover that up or alter it in any way.

Second, if you are going to age any sort of beverage in your barrel, then you may be worried about that varnish reaching and ruining the spirit or other liquid you’ve got stored away for a rainy day.

To that point, we’re confident that you can stop worrying as long as you use a food safe varnish or other type of wood finish. The varnish shouldn’t penetrate deep enough into the wood to affect any sort of flavor or smell of your aging beverage. Even if the finish does reach to a certain depth, the effect won’t be noticeable if you have allowed the coats to dry before filling the barrel and used a food safe product.

Finally, you may want to not varnish your barrel until it finishes maturing any contents in general. The barrels will still add flavor no matter what route you take, but by sealing the barrel with protective coats, you are limiting the amount the barrel can breathe. Oxygen entering from the outside of the barrel is part of the aging process. Varnish could interfere with a portion of that process.

Now, you might think slowing the aging process would be OK, all you have to do is account for more time, right? Not quite. Again, sealing up the barrel affects one part of the aging process. Results could be different, but that’s what experimenting is for!

Tips for varnishing your barrel

So, to review, if you do decide to varnish a small oak maturing barrel, please keep a few suggestions in mind:

1. Choose a food safe varnish or other type of food safe finish. These will be labeled as such and there are plenty of product recommendations from other resources out there.

2. Follow the instructions on whatever product you choose and remember to let it dry completely before filling the barrel. Drying times will vary by product and number of coats applied.

3. Consider how long you want to age the barrel’s contents. Adding a coat of some types of varnish could lengthen part of the aging process and deliver different results because the barrel will not breath as much. You could always select a breathable finishing option, such as oil-based polyurethane.

    Time to order a barrel?

    Small oak aging liter barrels of varying sizes on stands

    Ready to get a small barrel for aging bourbon, whiskey or perhaps a custom concoction of cocktails? We have a variety of sizes to choose from – also with engraving options for extra personalization.


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