real ale) is young beer that has been placed in small, metal, English
casks called firkins. In the sealed firkin the beer undergoes a
special conditioning process whereby the yeast produces carbonation and
wonderful flavor components and then settles to the bottom of the
cask. After a time, excess carbonation is vented and a serving
tap is hammered into a spout on the cask. The beer is served
without pasteurization or additions of artificial carbon dioxide or
other gasses. This is soft, fresh, living beer the way it was
meant to be served!
Tips on how to
condition and serve a good cask ale:
- Clean and sanitize
the cask thoroughly with caustic, and be sure to brush and clean both
openings. Seal the small opening at the end of the cask first.
- Using the large
center opening, add your beer to
the cask at the end of primary fermentation with enough sugar and yeast
to carbonate it lightly. If the beer has little to no residual
sugar, about 6.5 ounces of dextrose corn sugar will lightly carbonate a
gallon firkin. Fill the cask all the way and
remember to use a fining of your choice (gelatin works well). If
a dry-hop bag is added to the cask, try to add a large, sanitized
piece of stainless steel to the bag to make it sink a bit and
not clog the top bung
during later spiling/venting. Seal the cask with the large
- High-gravity beers
can condition at 55-65 degrees F for weeks or months. A 5% abv
ale should be ready to soft spile in 7-10 days or
- When you think the
beer has conditioned and built up some carbonation, set it up level and
horizontally on its wooden platform (stillage) with the large, center
bung up. Keep the cask
in horizontal stillage for a few days as close to 50-55 degrees F as
- 1-2 days before
serving, hammer in a dry SOFT spile through the middle depression on
large, center bung of the cask. Beer and gas should escape
through the soft spile. This is done to check the amount of
carbonation and allow excess gas to be vented slowly (so not to dredge
up sediment). When the venting slows, wipe off the soft
spile. When it takes three seconds or longer for beer to flow
back through the spile, this means the cask is probably ready for a
hard spile. With ALL spiles, leave the top one-third of the spile
showing out of the bung so you will be able to grab the spile with
pliers when it’s time to remove it. There is no need to sanitize
the spiles. (NOTE: If you
have plenty of time, sometimes it works just as well to skip the soft
spile and go ahead and hammer in a hard, wooden spile 3-4 days before
serving. Wooden hard spiles will SLOWLY vent excess gas over
1-2 days. Replace hard spiles that become really soaked through.)
- Remove the soft
spile SLOWLY with a set of pliers. If you feel pressure begin to
push up the spile, be ready with your mallet and another soft
spile. Hop bags and yeast can sometimes clog the soft spile and
make it look like the carbon dioxide is done venting. Often you
will have a stream of beer come out when the soft spile is
removed. If so, quickly hammer in another soft spile and keep
watching the venting – you may have to use 2-3 soft spiles (or more) to
get to the correct level of carbonation. It always helps to have
a towel ready.
- When you remove the
soft spile and only get a puff of gas (little to no beer venting from
hammer in a hard spile (again, only two-thirds of the way in so you can
pull it out later). Some hard spiles will still vent a tiny
amount over time – this is OK – if the hard spile gets really soaked,
pull out the hard spile and replace it with another.
- Hammer in your
sanitized serving tap (into the middle of the sealed, smaller bung at
the end of the cask) a few hours before you are ready to start
serving. Be sure the tap is closed when you hammer it in and the
hard spile is in place.
- If you must move
the cask a short distance from the stillage area to the serving area,
do so very gently,
keep it level, and then give the cask a few hours to
settle. NEVER shake, roll, up-right or jostle a cask before serving.
- The cask should
really be kept around 50-55 degrees F for the entire serving
time. Cask ale served at room temperature does NOT last long and
is NOT usually very pleasant.
- When you are ready
to serve, pour some beer into a glass to test the internal pressure of
the cask. When the beer flows very slowly into the glass, remove
the hard spile with pliers, place a damp towel over
the top of the cask (to cover the empty spile hole and keep the cask
cool), and start serving from the tap. Never draw beer through
with a spile in the cask.
- Please remember that putting filtered bright beer with CO2 into a cask
doesn't constitute cask ale. All cask ales should be placed into casks
unfiltered with a little residual sugar and yeast to naturally carbonate the
beer in the cask. All cask ales should have sediment. If a cask is rolled out,
immediately tapped, and pours clear, it is not real cask ale.
- Give cask ales plenty of time to drop bright and form the sediment
layer. Don't rush things.
- Use good finings - isinglass, gelatin, etc. And condition casks at cool
temperatures (50-60 degrees F). Warm conditioning temps make for exploding
casks. Cask ales can't be shipped in warm months on non-refrigerated trucks.
- Cask ale can't be delivered and served the same day. Please never do this.
A cask should have at least 24-48 hours in very cool horizontal stillage
position before being served. If you cask arrives the day of tapping,
immediately set the cask in cool stillage position, and put the tapping off
until the next day or next week. This is better than serving murky beer.
- Casks should never be up-righted or jostled prior to serving. Stable
stillage position is important.
- Don't soft spile just a few minutes before trying to serve. This often is
not enough time. Vigorous soft spiling also dredges up sediment and make the
- Wooden hard spiles from UKBrewing.com will typically vent
pressure above 5 PSI or so - just right for a cask. But the HARD spiles take 1-2
days to fully vent the cask down to 5 or less PSI. Soft spiles vent faster, but
do dredge up sediment at times. If you have a day or two, just use a hard spile
to vent -- 90% of the time, this works well. If any spile is blocked by a hop
bag or leaf hops, it will vent MUCH slower or stop all-together.
- Murky, cloudy cask beer is no fun. This is a sign that the beer might still
be working (too much residual sugar) and hasn't been given time to drop bright.
It's also possible that the cask was up-righted or shaken before serving.
Infection could also the issue, but taste and aroma will give this away.
- Be sure casks are served no warmer that 55 degrees F. Cask ale should never
be served warm.
- Don't seal the large top bung (shive) with a hop sock string sticking out.
This can lead to infection, and the bag will float near the bung and make
spiling and venting problematic. It's best to put the hop bag into the cask with
a bit of clean stainless steel to make the hop bag end up in the belly of the
cask (safely away from either of the two bungs).
- If a gravity tap plugs up with sediment during serving, it means that the
cask has not had time to drop bright. Never upright the cask and pull out the
tap to clear the blockage (your cask will be ruined by sediment). Rather, have
some clip corks on hand. Keep the cask in horizontal position, put the hard
spile back in, put a bucket under the tap, rock the tap gently by hand to remove
it, and slap in the clip cork to seal (you will just loose a little beer).
Unscrew the two pieces of the gravity tap, clear the tap screen (or temporarily
remove the screen), and hammer the tap back without removing the clip cork - the
soft clip cork just gets hammered into the cask. This way, a seal is
For casks and all supplies, check out UK BREWING SUPPLIES, www.ukbrewing.com, phone
I hope all this is clear, and please feel free to E-MAIL me with any
questions or suggestions. I encourage you will prepare and serve
cask ale soon -- your customers will love it!