From robust Reds to delicate Whites, classic Chiantis and bold Bordeaux and scintillating Chardonnay, whether you sing “La Brindisi” or of “Days of Wine and Roses,” wine plays a huge part in our life – and always has.
A passion for wine is splashed across the pages of world literature, from Shakespeare’s sack-swilling Falstaff to Poe’s “Cask of Amontillado,” imbibed in the Bible, Balzac, Borges, and beyond.
But what about the barrels storing all that wine?
Whether you’re a wine industry professional yourself or simply love storing vast quantities of it, wine barrels are an essential part of proper transportation and storage.
One of the biggest issues faced by barrels storing any alcohol is shrinkage.
The best way to combat that is to practice good general barrel caretaking while taking specific steps to reduce the risk of shrinkage and combat it where possible.
This guide can help you do just that.
1 – Keep Barrels From Drying Out
Dry wines may be your thing, but dry barrels definitely shouldn’t be.
While you don’t want your barrels to be sopping wet (and we’ll touch on that later) letting your barrels dry out is a surefire way for it to shrink and shrivel up. This, in turn, can cause any metal bands to loosen and rust, which in turn can cause the barrel to lose integrity.
If the bands come loose, the barrel will have to be coopered (that is, recrafted) all over again.
2 – Take Care of the Metal Bands
All of which is to say that keeping the metal bands in good condition is one of if not the most important thing you can do to ensure that the barrels remain in good condition. It’s a vicious circle – barrel shrinkage can cause the bands to come loose, which can cause the barrels to further shrink and degrade.
One thing barrel makers do to try and combat this is to galvanize the metal bands to help protect them against rusting. If your bands are not already treated this way, you’ll want to look into some galvanizing or anticorrosive spray or paint to protect them against moisture.
3 – Water Versus Ice
For as important as it is to ensure that your barrels don’t dry out, you might wonder if there’s a danger in going too far the other way and letting your barrels get wet.
However, water actually causes barrels to swell, with the metal rings holding them in place as the wood soaks it up. While that doesn’t mean you should drench your barrels, lest they expand too much, it means that water isn’t a likely cause of shrinkage.
However, that doesn’t mean it can’t cause problems from your barrel in other forms. If water is allowed to gather at the bottom and freeze in cold weather, it can exert pressure from the bottom up, causing severe damage.
4 – The Humidity Issue
In the absence of enough moisture, wood can dry out fast.
This is due to the larger issue of cellulose needing moisture for the cell walls to stay healthy.
That means making sure that there is at least some humidity in the space where the barrels are being kept.
Even so, you want to make sure this is done in moderation as well. If there is too much humidity, you may find that the barrels start to warp, which can cause the rings to become loose.
Whether or not that leads to shrinkage, this is as undesirable too, letting it shrink and dry out due to too little humidity.
The range that is acceptable for preventing your barrel from warping or shrinking starts at no less than 40% humidity. You’ll see anywhere from 50% up to 65% or even 75% listed as the proper ceiling, so pick a starting range and heighten or lower the humidity as needed.
5 – Maintain the Right Temperature
In addition to humidity, keeping barrels at a temperature that is too hot for them can cause them to start to dry out.
Unsurprisingly, this can often go hand in hand with a lack of humidity. Deserts aren’t just dry and lacking in humidity but typically very hot for much of the year as well.
The result is an environment that can dry out wood in searing temperatures with little to no humidity to replace it.
However, heat itself doesn’t cause the wood in your barrels to shrink. Instead, it is once again connected to humidity, as more heat can cause the humidity to drop.
For that reason, you should not keep wooden wine barrels at less than 55 degrees Fahrenheit.
6 – Preserve the Barrel with SO2
To keep the barrels in the best condition possible and prevent spoilage as well as shrinkage, you may want to consider burning the sulfur inside of the barrels and preventing it with sulfur dioxide SO2.
Make sure you work in an area that is well-ventilated, and avoid inhaling the SO2.
Once a month, check to see if there is any SO2 present. If there is, repeat the process.
The problem with this method, however, is that it may actually cause shrinkage over time.
7 – Other Ways to Preserve Wooden Wine Barrels
Thankfully, there are a few ways you can preserve your wine barrels without risking shrinkage.
For example, you can create a holding solution that will keep the wood in good condition.
Use a ration of 1 teaspoon of citric acid and 1.5 teaspoons of potassium metabisulfite for every gallon of volume, and dissolve this into hot water.
Once you have done this, you’ll want to fill the barrel about 2/3 of the way up with water and add the holding solution before adding a bit more cool water to top things up and cool things down.
Bung the barrel, and you’re good to go.
This solution should be topped up at least once per month to replace the amount of solution that may be lost due to evaporation as well as the absorption of water into the wood.
The good thing about using this holding solution and keeping it from shrinking is that, when stored in the right conditions, it should be able to preserve your barrel indefinitely.
While storing it, rotate the barrel 45 degrees or so every time you top it up.
Make sure that the bung and area around it remains soaked. This last part is essential for preventing the barrel from drying out and thus shrinking from this point outward.
Another method for dealing with spoilage that may lead to shrinkage is to fill the barrel 2/3 of the way with cool water and then add an alkaline solution. The latter can be sodium percarbonate or sodium carbonate at a rate of 1 tsp for mild spoilage and up to 3 tsp for bigger spoilage issues.
Allow the barrel to soak overnight
All of these steps can help prevent your wine barrels from shrinking.
Even so, the first reason they shrink really is the simplest, and the one we said at the beginning – they get dry and hot.
Keep your wine barrels in a cool, climate-controlled, appropriately humidified area, and you’ll be able to store and keep wine as a part of your life and livelihood for years to come.
I have two Associate’s degrees, one in Medical Assisting and the other in Computer Technician, and I am roughly five classes from a bachelor’s degree. Though I never ended up working in the medical field, I have five and a half years of experience in IT. I recently became a stay-at-home mom to my two young boys, and I’m so excited to start this adventure with them! In my spare time, I love to bake and read pretty much anything I can get my hands on.
Thursday 25th of November 2021
I have a new 25lt barrel which has also just been charred. Can I rather submerge the barrel in water, or keep it moist outside, in order to keep it from shrinking as I don't want to lose the char and flavor if I fill it with water?