While the art of brewing beer dates back thousands of years, beer canning is a relatively modern innovation. It wasn’t until 1935 that the first canned beers appeared on store shelves. But have you ever wondered how beer actually gets into those sleek aluminum cans?
Thanks to advancements in machinery and automation, modern beer canning has evolved into an efficient, high-speed operation. Here’s a step-by-step guide to how breweries bring your favorite beverage from tank to can:
Step 1: Loading Empty Cans
The process begins with stacks of empty aluminum cans, which enter the canning line in one of two ways:
Automatic canning: In larger breweries or high-volume facilities, a depalletizer lifts empty cans off stacked pallets and feeds them directly onto a conveyor belt.
Manual or semi-automatic canning: Smaller operations may require workers to manually place each empty can onto the line.
Regardless of the system, these cans start their journey lidless—essentially acting as open cups waiting to be filled.
Step 2: Rinsing the Cans
Cleanliness is paramount. Every can—whether newly manufactured or recycled—is thoroughly rinsed with sterile water. This is often done using a rotary rinser, a device that flips the cans upside down, rinses the interior, and then places them upright again, ready for the next step.
Step 3: Purging Oxygen
Before filling, any residual oxygen inside the cans must be removed, as oxygen can degrade beer quality and shorten shelf life. A stream of carbon dioxide (CO₂) is injected into each can from the bottom up, displacing the oxygen to maintain freshness and preserve flavor.
Step 4: Filling with Beer
With oxygen removed, the cans move to the filling station. A precision nozzle—often Teflon-coated—descends into each can and fills it with freshly brewed beer. High-capacity systems feature multiple filling heads to handle large volumes simultaneously. To compensate for any spillage and ensure consistency, machines typically fill slightly above the target volume.
Step 5: Placing the Lids
Next, the lids—often referred to as can “ends”—are applied. These aluminum tops are positioned over the filled cans. In some setups, nitrogen is sprayed into the headspace to push out any lingering oxygen before sealing.
Step 6: Seaming the Can
Seaming is the critical step that ensures the can is airtight. Each filled can is lifted into a seamer where two rollers perform a double-seal operation—firmly joining the lid to the body of the can. This airtight seal locks in freshness and prevents leaks.
Step 7: Rinsing and Drying the Exterior
As the cans travel along the line, minor beer spills are inevitable. To ensure a clean and professional appearance, the cans are rinsed and then passed through a high-speed air blower that dries the surface, preparing them for labeling.
Step 8: Quality Control
At this point, a quality control system checks for any underfilled cans, commonly referred to as “low fills.” These are removed from the line. Accurate fill levels are essential not only for customer satisfaction but also for regulatory compliance.
Step 9: Labeling
If the cans are not pre-printed, labeling happens now. Breweries typically use one of two methods:
Pressure-sensitive labels: Pre-printed labels are wrapped around the cans using a high-speed applicator.
Shrink sleeves: A plastic sleeve is placed over each can, and then heat is applied so the sleeve shrinks to fit perfectly.
During this stage, breweries also add vital information such as the production or expiration date.
Step 10: Packing for Distribution
Finally, the finished cans are grouped into 4- or 6-packs. Smaller breweries often do this manually using plastic holders, while larger facilities use automated packers. The packs are then boxed, palletized, and made ready for shipment to stores, bars, and homes around the world.
The Final Pour Canning beer may seem simple on the surface, but it’s a sophisticated process that blends precision engineering with brewing artistry. Thanks to modern technology, beer lovers can enjoy fresh, flavorful brews in lightweight, portable cans—anytime, anywhere.
