Twice a year the coopers at Pilsner Urquell undertake the job of re-pitching and rolling the large lagering barrels which are still used to mature beer in the brewery cellars. It’s an amazing process taking a lot of skill and hard work.
But first we thought you may be interested in watching a short video on how these massive barrels are built…
Since 1842, they have produced beer in wooden barrels and each of the barrels needs to be looked after to ensure the beer is exactly as they want it to be and to make sure the barrel can stay in use – and some of the barrels are over 100 years old.
‘Pitching’ is a process whereby we line the insides of the large oak barrels with ‘pitch’ ensuring that the beer doesn’t contact the wood (if it did this then it’d transfer qualities into the brew, which is something they are looking to avoid, ensuring they get a consistent flavour).
But adding the pitch, especially to the largest barrels, is certainly not an easy job…
Pitch is made from resin of evergreen trees, primarily pines, plus parafin and oil. Pilsner Urquell uses resin from the United States (some of this was imported over 40 years ago and they’re still using it), Canada and China in our own unique and secret recipe.
The resins, which are thick and black and leave an acrid smoke in the air, are cooked for a few hours, reaching 200°C.
Meanwhile, the barrels are removed from the cellars to the open yard next to the coopers’ workshop.
When the pitch is ready, we can begin. First, hot air is blown inside the barrel using a gas heater – this is to match the temperatures of the wood and the pitch, allowing for a better, smoother application.
Then the shiny dark pitch is ladled from the mixer into large metal buckets, being extra careful because of the extremely high temperatures.
And it’s the high temperature of the pitch which means the barrels need to be ‘rolled’ – it’s not possible to coat the whole inside of the barrel any other way when they are so large.
So the pitch is added, the barrel is sealed and the whole team of coopers gather round, ready to rock and roll.
Then with one man shouting orders, the team clasp the high sides and with the help of a wooden plank force it into a roll.
The barrel tumbles over onto its head and the momentum carries it into a second roll.
Finally the barrel comes to rest, rocking on its giant, groaning side.
And there’s no time to spare as a side plug is opened up, the excess pitch is drained out (around three-times the amount needed is what’s originally added) and the top hole opened in a steaming, gushing release of hot smoke.
The barrel is then left open for the pitch to dry – within an hour it’s possible to put a hand inside the barrel and feel the smooth pitch, now only warm to the touch.
The coopers will typically do this to 12 barrels back-to-back, so it’s an important day in the brewery and one which demonstrates the expertise of the coopers and our commitment to maintaining this traditional craft in the modern age.
Watch the pitching of the barrels – a 2 minute lesson on the process…
Source: Pilsner Urquell