The Advanced Process of Keg Filling in Commercial Breweries

Commercial breweries have evolved beyond simple on-site keg filling to incorporate sophisticated and automated systems that ensure high-quality, consistent, and hygienic beer products. This article explores the detailed process of keg filling used in some of the largest breweries, from loading kegs to final CO2 pressure.

Preparation and Loading of Kegs

The keg filling process begins with the loading of empty kegs onto a conveyor. In some breweries, robots are used to handle this task, allowing for a more precise and efficient operation. Cameras may be installed to verify the correct alignment and integrity of the spear (spigot) that will be inserted into the keg. Some breweries may also use a device to ensure the spear is properly secured before the keg is inverting.

The keg inversion is a crucial step in the process, as it allows for thorough cleaning and preparation of the keg for filling. The inversion process may be performed in a spray tunnel, which not only inverts the keg but also provides an external wash. This process removes labels, date codes, and performs a cosmetic clean-up, ensuring the keg is free from contamination.

Keg Filling Line Process

The next stage involves the actual filling of the keg. Large breweries often use multiple parallel filling lines, each equipped with several filling heads, allowing for significantly higher efficiency. A conveyor system transports the inverted keg to a filling head, where a ram clamps the keg in place, and an opening head pushes the keg valves open.

The filling process typically includes several steps to ensure hygiene and quality:

Depressurize and Drain: The keg is first depressurized to remove any remaining liquid or air. Water Rinse: A water rinse is performed to clean the interior of the keg. Compressed Air Purge: Compressed air is used to further clean and dry the keg. Caustic Clean: If needed, a caustic or detergent clean is performed to ensure thorough sanitization. This step may be skipped if caustic cleaning is done before. Steam Sterilization: The keg is pressurized with steam to hold at 60 seconds for sterilization. CO2 Pressure: The keg is vented and then pressurized with CO2. Filling with Beer: Carbonated beer is then filled into the keg.

Combining these steps on a single head is possible but less common. Multiple sequential heads are used to increase the throughput of the filling line, enabling more kegs to be filled in a given time.

Final Steps and Quality Assurance

Following the filling process, the keg is righted by an inverter, which is a simple yet effective mechanism. If present, a sanitizing agent may be sprayed into the spear to ensure hygiene. The keg is then capped, and a date code may be applied. The keg is then passed over a check weigher to ensure it meets the required weight, and any empty or under-filled kegs are rejected.

In the final step, robots are often used to de-palletize the keg and place it onto a pallet for distribution. The same robot that handled empty kegs at the beginning can be repurposed for this task, reducing the need for additional labor.

Alternative Methods

Commercial breweries with less budget may opt for simpler methods. For instance, a brewery will fill the keg with CO2 for a period, typically 3 days, before filling it with carbonated beer. Larger breweries, especially those with budget, may use a brite tank to carbonate the beer first, ensuring a more consistent and uniform product.

Brewers can choose plastic or metal kegs based on the specific needs of their operation. Plastic kegs are more portable and eco-friendly, while metal kegs offer better durability and are reusable for multiple shipments.

Conclusion

The advanced process of keg filling in commercial breweries ensures that the final product is of high quality, hygienic, and free from contamination. The use of automation and detailed cleaning processes greatly reduces oxygen pickup, which is crucial for maintaining the beer's freshness and shelf-life.

Whether a brewery uses sophisticated automated systems or simpler manual methods, the key is to maintain high standards of quality and hygiene to provide customers with the best possible beer.

By understanding and implementing these processes, commercial breweries can ensure consistency, reliability, and customer satisfaction.