Behind the brewery doors: canning day at Wildcraft

Those rows of shiny, empty cans on our homepage might not look particularly exciting yet. But they're about to become the final home for beer we've spent weeks brewing and looking after.

For the first instalment of our brewery journal, we're opening the doors at Church Farm, Smallburgh, for a closer look at canning day. It's a job where getting the details right matters just as much as it does in the brewhouse.

Brewed here. Canned here.

We can our beer at the brewery, using our Microcan IMP2 filling and seaming machine. Keeping packaging here means we see the beer through from brewing to the finished can, ready for your fridge.

But canning isn't simply a case of turning on a tap and putting a lid on. The beer needs to be ready, the equipment needs to be clean and sanitised, and temperature, pressure and filling all need to work together. Get that balance wrong and a carefully brewed beer can lose quality before it even leaves the building.

Oxygen: useful at the start, unwelcome at the finish

Oxygen has a role early in brewing, when yeast needs it to get off to a healthy start. Once fermentation is finished, though, we work hard to keep oxygen pickup as low as possible.

Oxygen can dull the fresh character of a beer and lead to stale flavours. For a hop-led beer, that means losing some of the aroma and flavour we worked to build in the first place. Packaging is our last chance to protect that work.

Before filling, we purge the empty cans with CO₂. That means introducing carbon dioxide to displace the air inside and reduce the oxygen the beer encounters as it enters the can.

Purging is one part of the job. Careful handling through the filling and lid-seaming stages matters too. The aim is to minimise oxygen pickup throughout packaging, rather than assuming a quick puff of gas solves everything.

Cold beer, calm filling

By canning day, the beer is carbonated. We chill that carbonated beer right down before packaging — cold crashing it so the dissolved CO₂ is less inclined to escape during filling.

As beer warms, CO₂ is more likely to come out of solution. Sudden pressure changes and turbulence can also encourage that gas to break out. You know what happens when you open a warm, shaken can? That's the sort of enthusiasm we don't want on the filling line.

Instead of a tidy fill, you can end up with foam everywhere: on the machine, over the cans and on the floor. It wastes beer, makes consistent fills harder and means the carbonation isn't staying where we want it.

Keeping the beer cold and managing pressure and flow helps us fill smoothly and retain the right carbonation. A controlled foam cap can help displace air at the top of the can before the lid goes on. It's excessive, uncontrolled breakout we're trying to avoid. Temperature alone can't do all the work, so we pay attention to how the beer travels from the tank into each can.

The small seam with a big job

Once the can is filled, the lid needs to be secured. Our machine forms a seam by folding the lid and the can's rim together. That small ring of metal needs to keep the beer contained and protect it until you're ready to open it.

We carry out seam checks during the run. It's another detail you probably won't think about when you reach for a beer, but one that deserves our attention.

From our brewery to your fridge

Our 440ml cans are a way to take a bit of Wildcraft home, whether you're choosing a familiar favourite or trying something seasonal. Every beer in our range is vegan friendly and gluten free.

The colourful label might catch your eye first, but underneath it is all this quieter work: clean equipment, CO₂ purging, cold beer, careful filling and a secure seam. The goal is for you to enjoy the beer as we intended it.

Want to taste the result? Build your own beer box and choose what goes in your fridge next.

And if there's something else you've always wanted to know about life at the brewery, let us know. We'd like to make this journal a regular look behind the doors.