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Copyright, Jeff Stanley, 1999
WHAT IS DRAFT
Draft beer today
usually refers to beer that is packaged in some sort of large container
(5 gallons or more). The old English word draft (spelled draught) meant
"to pull" because cask conditioned ale was dispensed with a hand pump called
a beer engine.
Some packaged
beer is referred to as draft beer in a bottle because it is cold filtered
prior to packaging rather than pasteurized at very high temperatures. High
temperatures will kill the flavor of the beer. Keg beer is almost never
pasteurized. Beer that has not been pasteurized must be stored cold and
goes out of date much more quickly than packaged beer (usually 45 days
after the keg is filled).
Brewers, distributors,
and retailers all take great care and spend a lot of money to keep kegs
cold and get the product to the consumer as quickly as is possible. The
end result is much higher quality, brewery fresh beer. Draft beer is a
product that most people do not have at home and can only be enjoyed when
going out. It is also much cheaper per serving giving you the option to
deliver better value to your customers.
Keg Specifications
for U.S. 1/2 Barrel
Height of Keg
-------------------------23.3 Inches
Diameter of
Keg ---------------------16.0 - 17.0 Inches
Contents in
Ounces ----------------1984.0 Ounces
Contents in
Gallons -----------------15.5 Gallons
Contents in
Liters --------------------58.7 Liters
Full Keg Weight
----------------------160.5 Pounds
Empty Keg Weight
------------------29.7 Pounds
Beer Weight
---------------------------130.8 Pounds
12 oz. Case
Equivalent ------------6.8 Cases
12 oz Servings
-----------------------165
16 oz. servings
-----------------------124
DRAFT SYSTEMS
In the not so
distant past most all draft beer was stored under the bar in a large keg
cooler. In these simple draft systems beer travels through a short line,
about six-foot long, that runs up an air-cooled three-inch tube to a faucet.
This is always the prefered way to dispense beer and works well if you
sell only one or two brands of beer, allowing room behind your bar to store
all of your kegs. Unfortunately if you have six different brands on tap
and a back up for each, twelve kegs behind the bar tends to get in the
way. Wheeling a 160-pound keg from the back cooler through a busy kitchen
and restaurant at 7:30 on a Friday night isn't much better. The only solution
is to run the beer lines from a remote location to the bar. This is referred
to as a closed remote draft system, usually a glycol system.
GLYCOL DRAFT SYSTEMS
Draft beer must
be kept less than 42 degrees from the tap all the way to the faucet. If
the beer is not kept cold all the way to the faucet the quality of the
beer will suffer greatly. Glycol draft systems allow you to keep the beer
cold even if the lines are very long.
Glycol systems
have five major parts. One, a cooler large enough to store all of your
kegs. Two, an insulated trunk line that the beer runs through after it
leaves the storage cooler. Three, a power pack that refrigerates the trunk
line. Four, the gas system that maintains the beer's natural carbonation
and pushes the beer to the faucet. And five, the draft tower mounted proudly
on the bar.
AVOIDING PROBLEMS
Glycol systems
work perfectly and waste very little beer if they are designed, installed,
maintained, and used properly. Unfortunately most glycol systems fall short
in one of these four areas.
If the system
is not designed properly using all of the needed components it will waste
beer and your bartenders time by producing excessive foam. A draft system
is like a car. There are many parts on a car that are not needed to make
it run smoothly. But I wouldn't buy a car that did not have a gas gauge
no matter how well it ran. If you are cutting costs on a draft system make
sure they are cosmetic. Do not remove options that make the system work
better.
Make sure your
installer has done good work in the past. Get references to insure your
system is professionally installed. Ask lots of questions. There are no
stupid questions. Go see an example of his or her work if possible. A glycol
system is a big investment that will return large profits if installed
properly.
All draft systems,
especially those with long lines, must have preventative maintenance service
at least every two weeks. At the very least the lines should be cleaned
and the faucet should be removed and cleaned. The lines cleaner should
also check the temperature of the beer that is in the lines and the temperature
of the storage area during every cleaning. This will help weed out many
problems before they become beer wasters.
The bar staff
must be properly trained to pour beer, clean and store glassware, and to
recognize and report pouring problems. If the beer is pouring too fast,
or is foamy, it cannot be fixed if it is not reported. Customers will let
the server or bartender know if the beer does not taste right. Never pour
from a system that is not working properly. You will waste beer and loose
customers.
Glassware should
be "beer clean". Beer glasses that are not cleaned using a detergent designed
for beer glasses will cause both pouring and off taste problems. Petroleum
based detergents used to clean other glassware and restaurant dishes leave
a film on the glass that will cause co2 to break out of the beer. This
results in foamy, flat tasting beer with little or no head retention. A
beer served with no head on it does not look very appealing and is less
profitable. Glassware chillers can also cause problems. Placing glassware
in a cooler before it is allowed to dry after washing will not allow the
sanitiser used in the final rinse to evaporate. This can give your beer
an off taste. Freezing beer glasses should never be done for several reasons.
Moisture will condensate on the inside of the glass when it is removed
from the freezer even if it is put away dry. This will water down the beer.
This also creates a layer of ice inside of the glass that will cause a
lot of foam and waste driving up the beer cost. Most beers were intended
to be served between 38 and 50 degrees. Serving the beer too cold will
numb the customer's palate and remove much of the beer's flavor. It is
easy to spot a glass that is not beer clean. Bubbles in the beer will cling
to the inside of the glass and there will be large bubbles in the head.
Beer served in a beer clean glass will have no bubbles clinging to the
inside of the glass and have a tight head with small bubbles.
USING CO2 TO DISPENSE BEER
The gas system
is a very important part of any draft beer system. When a draft system
has very long lines it can mean the difference between a perfect system
and one that you regret purchasing. The gas system can easily effect both
the taste of the beer and how easy (or difficult) your draft system is
to pour from. All beers have some CO2 gas dissolved in them. American lagers
have a lot, many micros and imports have very little. The dissolved gas
level of the beer effects the "nose" of the beer and also the way it feels
and tastes in your mouth. A few beers that are served almost flat (Guinness
is one example) also have nitrogen gas dissolved in them so they will still
have a head on them.
When you are
using CO2 to dispense beer the beer is sensitive to picking up too much
gas (over carbonation), and also loosing gas (going flat). Whatever gas
you are using, it always comes into contact with the beer in the keg. The
gas entering the keg pushes down on the beer forcing it up a tube and out
into the draft system. When using 100% CO2 there is very little room for
error when deciding how much pressure is needed in the keg. If the temperature
of the beer raises 2 degrees F one more pound of pressure is needed. If
the temperature of the beer drops 2 degrees the pressure in the keg needs
to be reduced by one pound. Different brands of beer also need different
amounts of pressure. For example at 36 degrees, Coors needs 15psi, Budweiser
needs 12psi, Killians Lager needs 13psi, and Bass Ale needs 9psi. If the
pressure is more than 2psi out of calibration the carbonation level of
the beer will change causing off taste, pouring problems, or both.
In summary,
if the right qualified individual adjusts the CO2 pressure for each beer
properly, and if the temperature of the beer never changes more than plus
or minus 4 degrees, using CO2 is O.K.. In reality I do not recommend using
plain CO2 to dispense beer, especially with long lines. There are too many
things that can and will go wrong. Beer is far too expensive to waste.
USING BLENDED
GAS
(BEER GAS)
TO DISPENSE
BEER
Beer gas is a
very simple and very effective way to solve most draft problems. If the
temperature in your beer storage area does not remain constant due to high
traffic. Or if your trunk line is not at least as cold as your cooler forcing
you to raise your pressure above ideal, a blend will prevent over carbonation.
Beer gas will many times allow you to run all of your beers at the same
pressure solving problems caused by different beers flowing at different
rates.
BEER GAS DON'TS
As with anything else there is a wrong way and a right way to use beer gas. If you do not use the proper equipment beer gas can damage the beer and also be very expensive.
PRE-MIXED
VS ON SITE BLENDING
Beer gas is
available one of two ways. You can purchase beer gas already blended in
a CO2 bottle, or you can purchase a blender and make your own beer gas
on site.
Pre-mixed beer
gas (sometimes called aligal) is an option if you cannot afford to purchase
a blender. There are two drawbacks to using pre-mixed gas. First, it is
much more expensive over time than an on site blender. Pre-mixed gas is
about three times as expensive as buying nitrogen and CO2 to mix on site.
Second, there are few choices in blends when you buy pre-mixed. The available
blends are usually very low in co2 and are not right for everyone. Too
little co2 in the blend will cause the beer to loose it's natural carbonation
and go flat over time. Serving flat beer with no head can have a greater
negative effect on your beer cost than foaming problems caused by over
carbonation using pure co2.
Blending Gases
On Site
The only drawback
to using a good blender is the up front purchase price. A reliable blender
ranges in price from about $450 - $700. There are also plenty of mistakes
that can be made.
Some really cheap blenders such as the one pictured above will work even if they are out of one of the gasses. For example, if your nitrogen bottle is empty these blenders will dispense all CO2 causing severe over carbonation. Cheap blenders are also easy to adjust on site. This creates problems with the wrong people making adjustments that will cause damage to the beer. Once the correct blend is selected and the system is set up no further adjustment is necessary.
Some draft parts vendors also offer blenders that mix the CO2 with compressed air to save money on nitrogen. Compressed air will make your beer smell and taste bad in a very short period of time. I cannot emphasize this enough; AIR COMPRESSORS WILL RUIN YOUR BEER AND CHASE AWAY YOUR CUSTOMERS. A 240 cubic foot bottle of nitrogen costs between $15 and $30 and will dispense about 80 kegs.
I recommend using the McDantim Trumix-100 gas blender (or Trumix-200 if you sell a nitrogenated beer like Guinness). Many draft equipment suppliers sell it as a private label product. It is very accurate under a wide range of flow demands, has no moving parts to wear out, will not operate if one of the gas supplies has run out, and is tamper proof. The blender from Johnson Enterprises pictured below is a McDantim blender set up to produce two blends. One side is 55% co2 and 45% Nitrogen. This is for the ordinary beers being dispensed at 25 psi. The other side is 25% co2 and 75% nitrogen for Guinness.
Click
here to visit the Mcdantim web site. There is a lot more great info on
blended gases there.
FLOW OF BEER
(F.O.B.) STOPS
a.k.a. Draft
Foam Control (D.F.C.)
There is very little to say about these. They simply shut off the beer flow at the keg when it is empty preventing the lines from draining. This will save the as much as one gallon of beer you would otherwise waste trying to pack the lines every time you change a keg.
1.) Step one
illustrates normal operation. Beer enters the side and exits through the
bottom. The red check ball floats on top of the beer.
2.) Step two
shows the keg is empty and is filling the FOB stop with air from the empty
keg.
3.) Step three
shows that as the fob stop emptied the check ball prevented the air from
entering the main beer line.
When the bartender
is pouring beer and the keg goes empty the beer simply stops flowing from
the faucet. The bartender changes the keg in the normal way then opens
the vent on the top of the FOB (shown in blue). The vent lets the beer
enter the FOB from the new keg. Once the fob is full of beer (about two
seconds later) the check ball floats to the top and allows the beer to
flow normally. There is no need to let the beer run down the drain for
sixty seconds, as you would without the FOB stop.
PUMPS
Beer pumps solve
most of the same problems as blended gas. Beer pumps apply mechanical pressure
to the beer in the trunk line instead of using the pressure in the line
coming from the keg. This eliminates problems caused by beer in the trunk
line being warmer than the beer in the cooler, which results in either
over carbonation or beer going flat in the lines. They also prevent beers
set at different amounts of pressure from flowing at different rates. Pumps
allow you to avoid these problems without buying any gas other than CO2,
which is much cheaper over time.
They will not
prevent over carbonation problems caused by temperature changes in the
storage cooler. Because of this I recommend using this method only if your
cooler is for beer storage only and the kegs on line are always kept at
the same temperature. Pumps should not be used in high traffic or unreliable
coolers without blended gas.
Copyright, Jeffrey M. Stanley, 1999
