This beer category is defined as: beers aged in non-neutral wood. This can result in an intentional wood-influenced flavour effect (vanilla, caramel, toast), flavours derived from previously aged alcohol in the wood (bourbon, whiskey, sherry, tequila), as well as the action of microorganisms living in the wood. Although darker or more alcoholic styles have been popular choices, barrel ageing can benefit a wide range of base beer styles.

One of the best ways to brew a beer with a memorable and nuanced flavour that you will savour with each sip is to age it in barrels.

What is Barrel-Ageing?

Barrel-ageing is a fermentation process that has been used for years.

It first appeared on the craft beer scene in the 1900s, when brewers began experimenting with storing beer in old whiskey barrels.

They discovered that by ageing the beer in these barrels, they could achieve distinct flavours for their beer. As a result, they were able to develop unique flavour profiles that piqued their customers’ interest in their products.

The Barrel Ageing Process

Beer is barrel aged in the same way that wine and spirits are. The barrel is usually made of wood and has previously been used to age wine, other spirits such as bourbon, or even maple syrup.

The barrel wood has a significant impact on the flavour that is imparted to your beer during the ageing process. The most common wood used is oak.
Although oak is a watertight wood, it is porous, allowing the beer to soak into the wood and absorb some of the oak’s flavours.

Barrels are typically charred on the inside in order to achieve a light, medium, or heavy toast. The strength of the flavour imparted by the barrel is determined by the toast.

However, ageing beer is more complicated than simply pouring it into a barrel and waiting a while. Beer maturation can take anywhere from 6 months to years. Different beers require varying amounts of barrel ageing to fully develop the best flavour profile.

Advantages of Barrel Ageing Your Beers

There are numerous advantages to barrel-ageing your beers. All of the benefits are related to the flavour of the beer and how it tastes in its final product.

For starters, barrel-ageing beer reduces harsh notes in the beer. This contributes to a softer flavour that is gentler on the tongue. This makes it a particularly advantageous process for strong beers.

Another advantage of barrel-ageing is that the flavours can blend together. While the beer is stored in the barrel, it absorbs flavours from the wood, giving it a distinct flavour. As a result, the flavour profile becomes more complex.

Finally, the barrel-ageing process brings out flavours in the beer that you might not notice otherwise. As a result, you get a one-of-a-kind beer experience that you wouldn’t get otherwise.

These flavour changes occur for a variety of reasons. Here are the main ways that barrel ageing affects beer flavour.

• Introduction of New Flavours
  • Because oak is a porous wood, barrel aged beer absorbs some of the wood’s flavours.
  • The most common woods used in barrel making are French oak and American oak. The flavour of American oak is stronger, with notes of vanilla, baking spices, dill, and coconut. French oak has more subtle chocolate and mild spice flavours.
  • A used barrel can also impart the flavours of whatever was previously aged in the barrel, such as wine, spirits, or even maple syrup, into the beer.
• Slow Oxygenation
  • When brewing beer, you know how important it is to keep oxygen out of the process. Early in the brewing process, too much oxygen can result in a musty beer. However, it is the slow exposure to oxygen that creates the subtle flavours in aged beer.
  • Slow oxygenation occurs when beer is aged in a barrel. Oxygen slowly leaks through the porous oak, resulting in a variety of flavours in the beer. Slow oxidation can help to round out bitterness in beers and bring out other flavour notes.
• Addition Of Microflora
  • Many different bacteria and wild yeasts live in barrels and are extracted into the beer as it ages. Though general brewing practises take great care to prevent contamination from bacteria other than brewing yeasts, barrel aged beers benefit from the other organisms with which they come into contact.
  • The numerous microflorae introduced during the barrel ageing process can actually introduce new flavours and mellow out the beer’s overall flavour profile.

Which Styles of Beer are Best for Ageing

In general, beer is best consumed as soon as possible after it has been brewed. This is due to the fact that exposure to oxygen can alter the flavour of the beer.

Ageing beer, on the other hand, can allow some beers to fully develop robust flavours. The success of barrel ageing beer is dependent on the type of beer.

Beers with a higher alcohol by volume (ABV) are more likely to develop a favourable flavour profile as they age. Furthermore, hoppier beers will most likely not age well. Despite their history of travelling overseas in barrels, IPAs are not suitable for ageing due the degradation of the hop flavours over time.

Stouts and porters are beer varieties that are widely acknowledged to benefit from ageing. However, they are not the only beers that can be aged.

During the ageing process, sour beers introduce the probiotic lactobacillus. As a result, the flavour is tart and fruity.

Wild-fermented beer is also becoming more popular. These beers may be exposed to outside air during the brewing process and do not take the same precautions to avoid contamination with yeasts other than the standard brewing yeasts.

Types of Barrels and How They Affect Your Beer

There are numerous types of barrels. Each one will impart a distinct flavour to your beer. As a result, each type of barrel has distinct advantages. Here are a few different types of barrels you can use and the benefits they provide for your beer.

• Rum Barrels
  • Rum barrels were among the first types of barrels used by brewers. These can hold any kind of rum. Initially, rum barrels were used to age bourbon or whisky.
  • They give your beer a delicious, alcoholic flavour that can really bring out the flavour of your beer. Coconut, banana, dark chocolate, and oak are some of the notes to expect from these barrels.
  • Dark beers are typically aged in rum barrels. Stouts complement the deep flavours instilled in the beers by the rum.
• Wine Barrels
  • Some of the best barrels for ageing sour beers are wine barrels. These beers are larger than most whiskies and are served in barrels. They also have a long shelf life, making them ideal for sour beer.
  • The best feature of these barrels is that they impart a fruity flavour to your beer. This eliminates the need to infuse fruit into the beer and clean up the mess afterwards.
  • Your beer will take on rich, smooth, and aromatic notes after being aged in a wine barrel. The fruity flavours of your beer will be influenced by the wine you use. Carefully selecting the wine barrel will allow you to influence the fruity notes that your beer picks up.
• Sherry Barrels
  • Sherry barrels are typically the largest barrels for ageing beer in. While it may take up a lot of room, it also provides you with a truly unique flavour profile.
  • When you flavour your beer with a sherry barrel, you can expect some distinct flavours to emerge in a relatively short period of time. You’ll get decent flavours, earthy tones, and the flavour of grape skins.
  • Because of these distinct flavours, sherry barrels are an excellent choice for ageing your beer. A sherry barrel is a good choice if you want something that stands out from the crowd.
• Whiskey Barrels
  • A whisky barrel is an ideal vessel for ageing clean beers that benefit from flavour infusion: For good reason, the imperial stout, bourbon, and oak trio is a classic.
• Bourbon Barrels
  • Last but not least is bourbon barrels. Bourbon barrels are typically used for anyone wanting to give their beer a bourbon flavour.
  • Bourbon-flavoured beers are one of the most popular types of beer out there. And, using a bourbon barrel can give you a more complex, woody flavour than you would get by simply infusing spirit into the beer itself.
  • It’s important to remember, however, that if you’re making a beer in a whiskey barrel you’ll likely only get one or two uses from the barrel. That makes barrel-ageing beer in this type of barrel a bit pricier.