The subject of draught beer complaints is a continual one, and could easily be the subject for a time consuming paper. Briefly then, and by way of review, the following detail may refresh our minds on the complexities of this product.

The primary complaints with draught which we encounter from day to day in the industry are; wild; flat; and off flavour.

The average storage temperature for draught beer is between 3 to 5°C (38 to 42°F). A degree either way will not basically affect the flavour or quality of the product. Between 7 to 10°C (44 to 50°F) flavour begins to deteriorate. This degenerative process is caused by micro-organisms present, as draught beer is not pasteurised. The process increases rapidly for each degree increase in temperature. On the other hand, under 1 degree C (34°F), the beer loses its taste appeal. Its brewery freshness and flavour is lost. Variance of a few degrees is acceptable, but 5°C (41°F) is the average serving temperature.

Beer is affected by grease or anything unsanitary. The beer lines, taps, vents and faucets must be cleaned regularly. Good quality detergents are essential, and are mandatory under the Public Health Act. Particular attention must be paid to the glasses. They should be used only for beer and never for a liquid such as milk. Beer glasses should be rinsed exclusively in facilities for beer glasses - never with dishes or other glasses where grease is present.

The pressure is also a vital factor in dispensing a perfect glass of beer. Beer in the keg will exert a pressure of its own within the keg. All breweries carbonate their draught beer somewhere between 2.3 and 2.7 volumes of carbon dioxide per volume of beer. The amount of gas or air pressure required to retain the natural gases in solution and simultaneously force the beer to the faucet is determined by the temperature of the beer in the keg and the carbon dioxide content of the keg.

Individual breweries vary only slightly in the amount of carbonation their particular beer contains. For this reason, various beers carbonated at 2.3 to 2.7 volumes will seldom vary internally more than 3 pounds pressure, assuming keg temperatures remain constant. For each degree C increase in temperature, the pressure will increase approximately 4 pounds per square inch. The warmer the beer, the greater the pressure within the keg. This increase of internal pressure necessitates increasing the counter pressure on the keg if the original carbonation is to stay in solution. The reverse is true when the temperature of the keg drops.

It is not advisable to tap a keg of beer immediately on delivery. Approximately 12 hours should be allowed for the temperature of the keg to become the same temperature as that of the storage cooler. We cannot emphasise strongly enough that this should be maintained at 5°C (41°F). Without knowing the exact temperature of a keg, a correct counter pressure cannot be applied.

It is obvious then that the pressure necessary on a keg of beer must be in excess of the normal keg pressure to produce a satisfactory glass of beer. The beer temperature in the keg should be a constant 5°C (41°F) or correct tapping procedures cannot be established.

An important word on tapping - always connect and turn on the gas supply before connecting up the beer faucet. If this procedure is not followed, some of the internal carbonation of the beer will be used in moving the beer into the beer line to the bar and under-carbonated beer will result. It is surprising how common this abysmal habit is in the trade. Secondly, once gas pressure is connected to a barrel, it should not be shut off. Again, loss of carbonation will result and flat beer will arrive at the faucet.

Thankfully, with the advent of the Sankey keg system, taps can now be removed without a loss of pressure from the keg. This single aperture system is now widely used and has all but eliminated many of the problems mentioned below.

You have probably gathered that this subject of temperature and pressure is the most important factor concerning draught beer, and we cannot emphasise strongly enough that the primary faults experienced in the trade are caused by lack of appreciation of the temperature-pressure relationship in draught beer.

Wild Beer

Wild beer can be eliminated if the following points are kept in mind:

1. Check the pressures. Too low a pressure will permit carbon dioxide to escape and results in flat beer. Too high a pressure on the keg conversely causes fast flow and wild beer.

2. Check the temperatures. Too high a temperature will permit carbon dioxide to escape. Regard anything over 5°C (41°F) with suspicion at the keg, not at the faucet. Remember, the system starts at the keg.

3. Balance the system so that the flow of beer is not too fast. Five litres per minute is a good flow rate for most systems.

4. Check beer lines for kinks, bends, dents, cleaning substances or bits of washers, etc.

5. Study the bartender's habits in handling the beer glass and faucet. Holding the glass too far from the faucet will cause foaming.

6. Check beer line length, as long runs should be refrigerated.

7. Check gauges for accuracy.

8. Check long beer lines for spotty insulation.

9. Check faucets for proper functioning. A "wire drawn" valve will cut the beer. The beer is agitated, separating the gas from the liquid, causing foaming.

10. Faucet warm up occurs when beer is not served frequently. A lag of 15 or 20 minutes will permit the beer in the faucet to warm to room temperatures resulting in two or three glasses of foam.

11. Temperature and pressure are the chief trouble points that should always be regarded with suspicion.

Flat Beer

Flat beer can be eliminated if the following points are kept in mind:

1. Not enough pressure on the keg.

2. Beer in the coils or keg is too cold.

3. Loose connections is the system, allowing the carbonation to escape.

4. Pressure was shut off at night or over a weekend in tandem with faulty connections.

5. Greasy glasses.

6. Holding the beer glass too close to the faucet.

7. Inaccurate pressure regulator.

8. Foreign matter in beer lines.

9. Fans moving quantities of air over beer glasses.

Remember, flat beer usually occurs:

i) When the carbon dioxide gas in the keg comes out of solution.

ii) When the beer is too cold.

iii) When the beer comes in contact with anything unsanitary or greasy.

iv) Leaking kegs, especially where the leakage is above the beer level, allowing the gas content of the beer to escape.

Cloudy and Unpalatable Beer

This condition is usually caused by:

1. Defective beer hoses.

2. Defective gas hoses which can become easily contaminated due to a defective valve or connection allowing beer into the gas lines. Gas lines are not cleaned in the usual cleaning routines.

3. An impure gas supply.

4. Sagging gas or beer lines.

5. Hot spots in beer lines.

6. Unsanitary beer lines or any part of the dispensing equipment.

7. Warm beer in the keg.

8. Excessive chilling, and especially freezing, causing clouding of the beer.

9. Poor rotation of the kegs. They should always be used on a FIFO system, in other words, used on a 'First In, First Out' basis.

10. Kegs kept on tap too long.

Above: Warehouse viewed from the southwest

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