Importance and History of the One-Way Beer Keg and PET Production

Preforms on the left.

Technological advances for business owners in any field are a welcome improvement to efficiency and productivity. In the world of craft-brewing, one of the best examples of such advancement is the modern packaging of one-way beer kegs and containers. The growth of the craft beer market has spawned an increased interest in this type of packaging from market players and the method and process of creating this product is equally as interesting as its success. 

Popular in both Europe and North America, the process helps decrease logistical and maintenance costs, as well as minimizing capital investments for brewery start-ups. It is particularly effective if your beer is shipped long distances like out-of-state or to other countries. Leading the charge in the sustainable keg world today is Petainer, a leading plastics recyclable beverage packaging company. Petainer is exemplary of the one-way keg production cycle model that uses a preform with a high degree of light and UV protection specially developed for producing polyethylene terephthalate or PET beer kegs.

To produce their one-way beer kegs, Petainer works with an Austrian manufacturer of blow molding equipment, PET Technologies GmbH, whose manufacturing capacities are based in Ukraine. PET Technologies GmbH single cavity automatic machine model APF-30  is capable of producing beer kegs of 15 L, 20 L and 30 L sizes at an output of up to 250 kegs per hour. Latest trends in development of PET bottle design avoid the once popular pentaloid bottle base in favor of a flat bottle base that helps better imitate a glass bottle. Also, a crown closure is now used instead of the traditional plastic threaded cap.

Creating the PET Container

To produce a PET container, manufacturers use a two-stage blow molding machine, a high-pressure air compressor, and a chiller which is a unit that circulates cold water to cool down the mold.  

The two-stage blow molding (or a reheat stretch blow molding – RSBM) processing cycle takes the mold through six key points: 

  Preform Loading → Preform Heating → Mold Clamping & Air Blowing→ Preform Cooling → Mold Opening → Container Discharge                                   

RSBM machines create the design of the PET container and apply long-term intense loads to solidify the molds. In fact, clamping force can reach sixty-tons or higher. Typically, molds are produced of high standard aluminum (special alloys) on 4- and 5-axis CNC machines. Some companies like PET Technologies GmbH have an R&D department and a specially equipped testing laboratory to develop container designs and to meet customers’ needs. 

As PET containers become more and more popular it is no surprise to see so many companies beginning to use this type of packaging. There are key advantages for the salability of PET containers. One advantage is that consumers see little to no taste differences compared to non-PET containers. Also, the PET is BPA-free, and packaging is convenient for recycling. 

While European countries have most notably been fans of one-way keg and PET container technology, the US beer market is no stranger to the process. The Olde Mecklenburg Brewery in North Carolina is  the first craft beer company to start a bulk use of PET bottles to package its products. Representatives there say they particularly enjoy the safety and effectiveness of using PET packaging. PET bottles, unlike aluminum cans are 100% BPA-free. In addition to keeping the beer pure, these recyclable bottles have several other advantages for craft breweries. In terms of appearance, PET bottles look exactly like industry standard glass long neck bottles, including secondary features such as labels and traditional steel crown closures (instead of twist-off plastic caps).

Continuous improvement and innovation in the area of sustainability for brewers is essential to the future of the industry. Manufacturers and consumers both have a responsibility to align with green efforts. With the technological developments in one-way keg and PET container engineering processes, breweries and beer manufacturers throughout the world can offer high-quality, highly attractive packaging for consumers with an environmental awareness that wasn’t possible even a decade ago.

If you liked reading this article, you may also enjoy: How to Choose the Right Beer Packaging.