Diary of a Beer Girl’s Isla Mercer explores the pros and cons of each vessel, and settles the debate once and for all.
Cask vs. keg. A debate with very strong minded advocates on either side but which is actually better? First, it’s best to explain exactly what the differences are between the two.
In a nutshell, casked beer tends to be less fizzy and served at 11-13°C through a handpull, whereas kegged beer is usually fizzier and served at a cooler temperature, generally between 2-8°C through a beer font.
So what causes these differences? Well actually, both casked and kegged beer are brewed in exactly the same way. However, casked beer is only partly ready before it goes into the cask. It needs to undergo a second fermentation which happens once it goes into the cask, along with a bit of sugar to react with the yeast already present.
A keg on the other hand is like a giant can of beer. The beer is filtered and generally made sterile before going into the keg so its contents are ready to drink.
Pubs need to take a lot more care of casked beer and the cellar temperature is very important as the beer is at its best when stored at 10- 14°C. Casked beer should really be drunk within a few days of opening as oxygen is beer’s worst enemy and causes the flavour to change very quickly.
If a pub doesn’t adhere to these two factors, the casked beers won’t taste right, so there’s a lot of onus on the pub to make sure the beer they pour reaches you in the condition the brewer intended it to!
Kegged beer however, offers much more leniency on the temperature of the pub cellar since, at the stage of it going into keg, it is completely ready to drink and no more chemical reactions take place. Kegged beer also lasts a lot longer since a keg is an air tight container so there is far less oxygen contact. The kegging process involves adding carbon dioxide to carbonate the beer which is why it is generally more fizzy.
“There’s a lot of onus on the pub to make sure the beer they pour reaches you in the condition the brewer intended it to!”
Casked beer on the other hand is carbonated via carbon dioxide being released naturally as a by-product from the yeast reacting with sugar to create alcohol. As a result, publicans often prefer kegged beer regardless of taste purely because it’s much easier to manage which is why it’s more readily available in pubs.
Some people consider casked beer to be old fashioned and kegs to be the vessel of choice for pioneering craft beers. It is true that there are an awful lot of very samey 3.8% blonde or bitter ales that are only sold in cask, but bland tasteless lagers are only sold in kegs.
Because the kegging process requires specialist equipment that can be quite costly, sometimes beers from the smallest, most exciting breweries are only available in cask. Also, a lot of pubs have restrictions on their kegs since big lager brands use kegs lines and therefore want to control what goes on them.
Publicans often have a lot more freedom with their cask lines so they can offer a much more varied range. So really both cask and keg have their fair share of new and exciting beers as well as bland and boring ones.
There is an argument upheld by cask advocates who say that beer shouldn’t be served too cold as cool temperatures numb our tongues and therefore inhibit beer flavour. This is why good whisky isn’t supposed to be served with ice.
This is a point I definitely agree with and when drinking at home, I rarely put beers in the fridge. However, some beers are so intense in flavour that the taste comes through despite being served at a cooler temperature. And sometimes, nothing will quench a thirst more than a nice, cold pint.
The extra fizz also works really nicely with some beers, giving the flavours a real lift. So, different beers suit different serving temperatures and different levels of carbonation. If you’ve never thought about what temperature you prefer your beer served at, try a little experiment with two of the same bottled beers, one you’ve cooled down in the fridge and the other at room temperature to see what the difference in taste is and which you like best.
In short, both cask beer and kegged beers have stereotypes which aren’t really true in today’s beer world and both have their pros and cons. In the cask vs. keg match, for me it’s a 1-1 draw and both sides should share a post-match pint whatever their preferred format!
Originally published in Issue 2 of our Flavourly magazine. Written by Isla Mercer.