Fermenting and aging beer in wooden barrels

The influence of the barrel on wine taste is recognized the world over, and wines aged in oak barrels - barriques - are prized and expensive. But less is said about the influence barrels have on beer. It's not about industrially brewed beer, where the containers are made of stainless steel and fiberglass, but craft beer, which has been making a strong comeback since the 90s. This trend can also be seen here, where it is no longer a problem to find beer with different flavors, stale or with a high alcohol content. Many of these processes for enriching beer with special flavors involve wooden barrel impregnated with various flavours.

Beer, the drink from which the expression honeymoon

It's not surprising that brewers think of the wooden cask when they want to add special flavors to beer. Wooden vessels have been used for 2000 years for fermenting, storing and transporting beer. But beer is much older. The first evidence of brewing dates back over 6000 years to the Sumerians and Babylonians. In The Epic of Ghilgames, wildlife Enkidu drank milk and beer like humans. The Sumerians' custom of giving young couples honey-sweetened beer is also linked to the honeymoon celebrated today by newlyweds. In those days, however, beer was kept in animal-skin containers or ceramic pots.

The Egyptians first procured the beer from the Babylonians and then began brewing it themselves. It was considered a special drink and was therefore offered to the gods and used in traditional medicine. The first drink tax is also linked to Egypt. Cleopatra, in order to raise the money to build a pyramid dedicated to her, put a tax on beer consumption. It was also used as a cure by the Romans, who had beer-based remedies for coughs and bee stings. The switch from ceramic pots to wooden casks took place during the Roman Empire, with the Gauls imposing the new method of storage and transportation. The Germanic peoples borrowed beer recipes from the Romans and obtained different tastes depending on the wood of the barrels in which they fermented the beer.

After the break-up of the Roman Empire, many lands were taken over by monasteries. Here they began brewing beer from various natural ingredients. Beer was considered a very nutritious food and was widely consumed during fasting. The beers were sometimes named after saints and because they couldn't explain why the taste was sometimes good and sometimes bad, fermentation was linked to the presence of spirits and witches. These supposed witches who spoiled the taste of the beer could even be burned at the stake. The last such event dates back to the 16th century.

In modern times brewing beer has been easier to control and replicate, which has led to it being brewed on an increasingly large scale. The emergence of taste-neutral materials - glass, and later stainless steel and fiberglass - meant that wooden casks were gradually phased out for fermentation, storage and transport. Industrially brewed beer was stable, reproducible in taste and affordable for everyone. But it had lost much of its personality, leading to a resurgence of craft brewers in the 80s and 90s. From there the phenomenon took off, with craft beers with distinctive tastes and flavors now everywhere.

Fermenting versus aging beer in oak barrels

The main beer-producing countries are in the northern part of the European continent. Beer caught on especially in countries that were not very suitable for growing vines because of cooler temperatures and shorter sunny periods. The Germans were the first to use wood to modify the taste of beer. Discovering that beer tasted different depending on the species used to make the cask, they tried to achieve new tastes by juggling these species. But the most important influence was oak. Even today, the oak barrel is still used to ferment traditional beer.

Although, in many cases, the cask has been replaced by stainless steel vessels, there have been brewers who have remained faithful to traditional brewing. True, stainless steel vessels are easier to clean, but they are inert and do not impart anything to the taste of the beer.
Wood is somewhat unpredictable compared to steel, but it has the advantage of flavor compounds and porosity, which allow microorganisms to participate in the process with repercussions on the taste and quality of the beer. The size of the keg is important, the smaller the container the greater the influence. The origin of the oak is also important, with large differences between casks made from European and American oak.

In the keg, the beer may ferment or go stale. For fermentThe mixture of grain, water and yeast is put directly into the oak barrel. During the process the sugars are converted into alcohol and the oak contributes tannins to the taste lemnos of the beer. The entire fermentation process takes place in the cask, which allows the oak to contribute to the final taste. The result is a more bitter, dense and full-bodied beer. As with wine ageing, barrel fermentation is sometimes replaced by adding oak chips to the fermenting vessel. This reduces costs.

Ageing Barrel fermentation is done after the beer has fermented. In this case barrels are used in which other alcoholic beverages have been aged: whisky, bourbon, rum, gin, tequila, wine. Brewers know where they want to end up and choose the barrel according to the desired end result.

Beer flavors from kegs used for other drinks

In general, aging beers have an alcohol content higher than 8%. During aging the color darkens, the beer becomes more full-bodied, with a more balanced, rounder taste. Both beers can be aged white as well as dark ones. Depending on the cask used, the beer may taste vanilla, caramel, nutty, nutty, dill, smoky, slightly sour, etc. The density, bitterness and color depend on the base from which it was made.

Bourbon casks are a common choice to impart caramel and vanilla flavors to beer. Single malt whisky casks add a smoky note. Wine casks give a more sour taste to the beer and add cherry, blackberry or raisin notes. The tannins from the red wine soaked in the cask give the taste an astringent note. The time the beer spends in the barrel is also important. A short aging takes away more of the flavor of the beer that has been in the barrel. A longer time will allow the beer to reach the burnt wood part of the barrel and extract notes of vanilla, coconut, cinnamon, anise, chocolate, coffee.

Brewers are also experimenting to better understand the role of the keg when adding flavors. For example, the same type of beer imperial ale (richer in alcohol and flavors) was aged the same time in bourbon, rum, fresh red wine, port and sherry casks. From the bourbon it took coconut, dill and sweet spices, from the rum - oak and dark chocolate, from the fresh wine - acid and wild notes, from the port - notes of cherries in chocolate, and from the sherry - grape skins and oak.

Romanian craft beer

Romania also produces many kinds of craft beers that taste more and more interesting. A Belgian-inspired beer appreciated by the Belgian ambassador in Bucharest was made by the Oriel craft brewery. The beer was fermented for a month in a stainless steel vat, then transferred to a Jack Daniels barrel where it was fermented for six months. The beer was then put into bottles and left to referment for 21 days, after which it was chilled for another 21 days. After eight and a half months, the beer was presented at an event attended by the Belgian ambassador. Full story here.

Tasting craft beers is just as interesting as tasting wines, and those aged in various barrels are truly special. If you get the chance, don't miss it.

I hope you find the above information interesting. As always, additions are welcome. And if you have any questions or queries, please leave them below in the space provided. I will be sure to reply