What’s the difference between cask and keg ales?

Answered by Frank Schwing

Cask and keg ales are two different ways of serving beer, each with its own unique characteristics and methods. Let’s delve into the differences between cask and keg ales in detail.

1. Brewing Process:
– Cask Ales: Cask ales are traditionally brewed using a process called “cask conditioning.” After primary fermentation, the beer is transferred to a cask or barrel along with some additional yeast and sugar. This allows for secondary fermentation to take place in the cask, resulting in natural carbonation.
– Keg Ales: Keg ales, on the other hand, are brewed using conventional methods and undergo primary fermentation. After fermentation, the beer is filtered, carbonated, and then kegged, ready for storage and serving.

2. Carbonation:
– Cask Ales: Cask beers do not have added gas. Instead, carbonation occurs naturally as a result of the secondary fermentation process in the cask. The live yeast consumes the added sugar, producing carbon dioxide, which is trapped in the cask, creating a gentle, natural carbonation.
– Keg Ales: Keg beers, on the contrary, are served with the addition of gas, such as carbon dioxide and sometimes nitrogen. These gases are injected into the keg under pressure, providing the desired level of carbonation.

3. Serving Temperature:
– Cask Ales: Cask beers are typically served at cellar temperature, which is around 11-13 degrees Celsius (52-55 degrees Fahrenheit). This slightly cooler temperature allows for the flavors and aromas of the beer to be more pronounced, giving a fuller taste experience.
– Keg Ales: Keg beers are commonly served at colder temperatures, typically between 3-8 degrees Celsius (37-46 degrees Fahrenheit). The colder serving temperature is preferred to enhance the crispness and refreshing qualities of the beer.

4. Maturation:
– Cask Ales: Cask-conditioned ales require time to mature and develop their flavors. They are often left in the cask for several days or even weeks, allowing the yeast to continue working and imparting unique characteristics to the beer.
– Keg Ales: Kegged beers are generally ready to serve immediately after carbonation. They do not undergo the extended maturation process required by cask ales.

5. Packaging:
– Cask Ales: Cask beers are typically served directly from the cask using a hand pump or gravity dispense. They are often consumed in traditional British pubs or beer festivals, where the casks are visible and tapped on-site.
– Keg Ales: Kegged beers are stored and transported in stainless steel or plastic kegs, which are pressurized and tapped using a gas-powered system. They are commonly found in bars, restaurants, and breweries that have draft systems.

The main differences between cask and keg ales lie in the brewing process, carbonation method, serving temperature, maturation time, and packaging. Cask ales offer a more traditional, naturally carbonated, and complex flavor experience, while keg ales provide a consistent and readily available option with controlled carbonation levels. Each style has its own charm and appeals to different beer enthusiasts.