What types of beer kegs are there?

You’ve surely noticed the beer kegs you see in bars. And if you visit a lot of beer bars, you’ll have realized that in some cases they can be very different. Why? It’s not just an aesthetic issue. Each format responds to specific needs, which we’ll explain below so you can identify them next time.

The stainless steel keg is a classic of the brewing industry. It is probably the most widespread type, the one you find in most bars and restaurants. There are two basic types: European (wide and low) and DIN (narrow and tall). Both types of keg come in 20, 25, 30 and 50-liter sizes, while the European model is also available in 16 liters. There is also the cask version of the metal keg used for low-carbonation English styles.

Also made of stainless steel is the Cornelius or Corny keg. It’s similar to European stainless steel kegs but with one key difference: the beer out line is separate from the valve used to inject gas; they don’t share the same coupler. They use ball‑lock or pin‑lock fittings for faster connection. Corny kegs were originally used to transport soft drinks, but today they are mainly used by homebrewers, as they allow for forced carbonation of beer and have a large opening at the top so you can add dry hops.

On the other hand, we have PET plastic kegs, which have become popular mainly with the rise of craft beer and for export. These are further divided into disposable and reusable. Kegs without an inner liner can only be used once, with exceptions such as the Dolium model.

However, there are different types of plastic kegs in which the beer is not in contact with the outer wall, but instead there is an inner bag (also made of PET plastic) that provides double protection for the beer. The most widely used and best-known is KeyKeg, the first to manufacture them. This way we prevent the outer container from degrading. These bags are not reusable. They must be discarded, although in some keg models, such as EcoFass, the keg itself can be reused; you just have to replace the bag.

In addition, beer transport is increasingly sustainable and some manufacturers are opting for environmentally friendly products such as EcoFass, EcoDraft, KeyKeg or EcoKeg; the last two are 100% recyclable.

Lastly, it’s worth mentioning that, although they are increasingly rare, there are still traditional wooden casks used as casks. There are also service tanks, which are becoming more widespread. These are an alternative to kegs but used for the same purpose, with the difference that they hold 1,000 liters of beer. As you can see, each type of keg offers different characteristics depending on the producer’s needs. Next time you visit a brewery and look over at the bar, you’ll be able to identify the model they’re using.