Glass Carboys vs Oak Barrels

The two most traditional vessels to age wine in at the amateur level is in either glass carboys or small oak barrels. Which is better? You’ll have to be the judge.

Glass Carboys

Glass carboys have been used as far back as the early 1800’s (per some historians), mainly to hold strong chemicals such as acids. Eventually these vessels were used in water coolers and by amateur wine makers.

Their use in wine making stemmed from the need to have a small and affordable container to ferment and age wine in. Plastic carboys did not come onto the scene until very recently. Thus amateur wine makers had to choose between a glass carboy or an oak barrel.

Here’s a cost breakdown between an oak barrel and a glass carboy.

Beyond cost there are several advantages to using a glass carboy over a barrel. For starters the glass carboy can be used over and over again indefinitely. They don’t have a shelf life, like a barrel does.

Glass does not impart any flavors or chemicals into your wine. This is convenient because we can use the same container to make wines with or without oak in the same vessel.

Oak chips are available in many forms from saw dust to cubes to spiral cut dowels. They can be purchased in all the same toasting levels that traditional barrels are made of.

Another benefit to using glass is that it does not harbor micro-organisms. The smooth finish of glass provides no place for micro-organisms to hide from sanitizer and it’s easy to clean.

So if a fermentation were to get spoiled by a stray micro-organism such as vinegar bacteria you merely have to clean out your carboy and you’re ready to go again.

There are some drawbacks to the glass carboys though. First of all they’re made of glass. When they break they shatter and turn into a lethal pile of shrapnel.

Second, they’re heavy which makes the first point that much more serious. In recent years plastic carboys have gained popularity because they’re lighter and don’t shatter. However, we’ll get into the glass vs. PET carboy debate at another time.

Wine Making Barrels

Oak barrels are the more traditional aging vessel for wine. By traditional I mean that they’ve been in use for a little over 2300 years. They came into common use around 350 BC by the Celts as a lightweight, portable container for shipping.

Along the way winemakers determined that the oak imparted desirable flavors to the wine aged in it. Specifically if that oak had been subjected to fire on the inside face of the staves. This is called toasting.

Prior to using barrels winemakers primarily used clay and concrete vessels. Obviously these were not that portable.

The use of oak as a building material likely stemmed from its structural integrity. While different woods may impart equally beneficial flavors they may not have been strong enough to be used as a barrel.

Barrels are often referred to as the winemaker’s spice cabinet. Different types of oak offer different flavor profiles. The inside face of the oak barrels are subjected to fire through a process called toasting.

Different toasts offer different flavors. Thus mixing and matching oaks and toasting offer the winemaker many flavoring options.

Today oak barrels are available as small as 5 gallons

For the modern winemaker barrels do have several drawbacks.

First, barrels are expensive when compared to glass carboys. Even small barrels for the amateur winemaker can cost a couple hundred dollars.

Bearing cost in mind another drawback to barrels is that they have a limited lifespan. Provided they are well cared for they can be used for up to seven years or so. However, after three or four years they impart little oak flavor to your wine.

If you want oak flavor from an older barrel you must increase the time it spends in the barrel. Thus you may need to age your red wines three or four years in an older oak barrel to pick up the oak you want.

Because barrels are made of wood which is porous they provide a nice home for micro-organisms to live even when there’s no wine in them. Should your wine be spoiled by a vinegar bacteria while in a barrel that barrel can never be used again.

The organisms can hole up in the pores of the wood staves and will infect your next wine. Using sulfur dioxide gas in the barrels does not kill the bacteria. It’s time to make a nice garden planter.

Lastly, barrels must be meticulously maintained. When your barrels are empty you must clean and sanitize them on a monthly basis to keep them in working order.

Oak Chips Aren’t Just for Amateurs

Through the use of oak chips though the same results can be obtained in glass carboys. In fact with a carboy you have more freedom to experiment with different oak toasting levels as well as oaks from different places.

Barrels on the other hand are set once they’re made. You can get barrels made from oak from different parts of the world and get different toasting, however, once they’ve been built that’s it. You have to buy different barrels to try something new.

If you think that oak chips are limited to the amateur or small-scale winemakers I would beg to differ. Texas Hills Vineyard in Johnson City Texas uses oak chips in large stainless steel fermentation tanks to impart oak flavors without having to use barrels.

They get all the oak flavor they want and they’re able to experiment with different oaks because they’re not tied to barrels that were made a certain way. With production levels at 16,000 cases of wine per year (roughly 38,400 gallons!) this is no small operation. They use some pretty impressive stainless steel fermentation tanks to make their wines which saves them the time and expense of maintaining barrels.

In order to replicate the micro-oxygenation process that wine undergoes in the barrel Texas Hills Winery uses small devices that go into their tanks micro-oxygenation technology to replicate the same oxygenation process barrels offer your wine.

Through this device they can control the micro-oxygenation process and actually simulate a longer aging period in a shorter amount of time by controlling the amount of oxygen introduced.

Please check out this great article by my friend Jeff Cope of Texas Wine Lover on Texas Hills Vineyard.