Inside BrewDog’s new Overworks sour beer facility

The Morning Advertiser ​headed to Ellon, Scotland, to check out the new brewery and its first beer releases.

The Overworks facility has been under construction since January 2017, and cost more than £4.5m to build. The venue holds ten 50hl Italian foudres, eight 100hl foudres, as well as a host of smaller barrels in which to age beer.

The brewhouse also boasts a 50hl coolship, which enables beers to be spontaneously fermented in a similar fashion to Belgian lambic-style sours.

First beers revealed

The first beers to be released from the facility have been produced using alternative, mixed culture methods of fermentation and barrel ageing. They include Pyraster – a pear sour aged in red wine barrels and fermented with yeast from locally sourced blackberries, and Mariangela – a blended saison with blush orange and strawberries aged for two months in an amphora (a clay vessel similar to a barrel).

The beers are produced using wort from the brewery’s 100hl brewhouse, which is then transferred to the Overworks facility prior to fermentation to avoid cross-contamination. They will be released for sale to the general public at the end of this month in BrewDog bars and online in bottles.

Brewing pedigree

Overworks is being run by Richard Kilcullen, former head of sour production at Wicked Weed. The American brewery was bought by Anheuser-Busch just months after Kilcullen’s departure in spring 2017.

Commenting on the decision to hire Kilcullen, BrewDog co-founder James Watt said: “I went to Wicked Weed about six months before they were bought out by AB InBev. I went to their Funkatorium and I was blown away by the sour beers they were making there at the time.

“I managed to spend some time with Richard, and persuaded him to give up America and come to the north-east of Scotland and help us introduce people in the UK to these modern, American sour beer styles.”

Investment and commitment

Kilcullen said the investment and commitment from BrewDog in Overworks were key factors in his decision to join the company.

“The project and level of investment here by these two [James Watt and Martin Dickie] is unreal,” he said. “I worked for one of the largest sour producers in America and it took us five and a half years to get to this kind of level.

“The equipment and investment has meant that everything is top of the line and it is a really exciting project to be a part of. However, the ingredient you cannot fake is time, and that is the biggest commitment for me. This level of outlay and laying these things to rest for as long as we have is painful for a fast-growing company, but you really taste it in the end product.”

Cross-contamination rules

The Overworks site has strict rules to avoid the cross contamination of regular BrewDog beers. The brewhouse is housed in a separate building to the main production facility, and visitors are required to enter through a ‘decontamination chamber’ fitted with antibacterial matting.

Brewers who come into contact with mixed cultures are also required to undertake a full outfit change before leaving Overworks and entering the main facility.

There is also a dedicated high-tech lab space on-site, which is run by the same in-house microbiologists from the main BrewDog facility.

The lab team hopes to eventually be able to take a single cells of isolated yeast strains strain from anywhere in the world and grow them to a point where there is enough healthy yeast to include in a production scale fermentation.