Daily draught quality checks a bar manager can do in ten minutes
Most draught problems give warning signs before they reach the customer. A cold room drifting up a degree, a gas cylinder running low, a tap that tastes faintly buttery. A short daily routine catches them. Here is the one we would hand to any bar manager, split into ten one minute checks.
Minute one: the cold room thermometer
Read the cold room temperature on a thermometer you trust, not only the controller display. The target for most draught systems is 2 to 4 °C. Write it on a log sheet with the time. A drift of a degree a day over a week is easy to miss without a log and easy to spot with one.
A glass of water or a bottle of beer left on a shelf with a probe in it gives a steadier reading than the air, which jumps every time the door opens.
Minute two: gas cylinders and regulators
Check the contents gauge or weight of each gas cylinder. Check each regulator reads its set pressure. Write both down. A regulator reading that has crept up or down since yesterday points to a faulty regulator or a leak.
Keep a spare full cylinder of each gas you use. Running out of gas mid service is avoidable.
If the bar uses more than one gas, such as CO2 for most taps and a nitrogen blend for stout, check each cylinder is connected to the right regulator. Cylinders get swapped in a hurry. A stout line accidentally put on pure CO2 will look fine today and pour badly by the end of the week.
Minutes three and four: pour every tap
Pour a small amount from every tap into a clean glass. You are looking for:
- A steady flow, about 60 ml per second.
- Foam of about 2 to 3 cm on a normal pour.
- No spluttering, which suggests a nearly empty keg or a gas problem.
- No excessive foam, which points to warm beer, wrong pressure or a dirty line.
Pour off any warm beer sitting in uncooled sections of line before you assess it.
Time one pour on each tap with a phone stopwatch once a week. A 500 ml glass should take about 8 to 9 seconds. A tap that has slowed to 12 seconds may have a blocked nozzle or a partly closed flow control. One that has sped up to 6 seconds may have a regulator drifting high.
Minutes five and six: taste every tap
Taste a small sample from each tap, about 30 ml. You are checking the beer is the beer it should be. Watch for these signs:
- Buttery or butterscotch: diacetyl, often from bacteria in a line due for cleaning.
- Sour or vinegar: bacterial contamination in the line or tap.
- Papery or stale: old beer or a keg stored warm.
- Metallic: worn fittings or an acidic beer on brass.
Taste with someone else where possible. Two palates catch more than one. Taste each tap in the same order every day, lightest beer first. Rinse with water between samples so a big IPA does not mask a fault in the lager after it. Our guide to a ten minute daily taste panel shows how to run it properly.
Minute seven: beer temperature in the glass
Put a probe thermometer into the first full glass from your longest line. The beer in the glass should be within about 1 °C of the cold room. If it is several degrees warmer, the line cooling is not reaching the tap. Our guide to python cooling covers the usual causes.
Write the reading on the log next to the cold room figure. Over a month the gap between the two numbers tells you whether the cooling is holding steady or slowly losing ground, which is far more useful than a single reading on a bad day.
Minute eight: glass cleanliness
Take three glasses at random from the clean stack. Wet each one, tip it out and look. Water should sheet off evenly. Pour a beer into one and watch: bubbles clinging to the sides mean a dirty glass. When the beer is drunk, clean glass leaves rings of foam lacing at each sip.
A failed glass test usually means detergent, rinse aid or washer temperature is wrong. Fix the washer before service.
Check where clean glasses are stored too. Glasses stacked rim down on a rubber mat or a shelf liner can pick up smells. Glasses near the kitchen can pick up grease from the air. Both kill foam.
Minute nine: taps, nozzles and drip trays
Check every nozzle came off its overnight soak clean and is refitted. Look for dried beer around faucets and sticky handles. Rinse drip trays and check drains run freely. Standing beer in a drip tray in a warm bar draws fruit flies within hours.
Minute ten: the line clean log
Look at the date of the last full line clean for each line. Most guidance, including the Brewers Association draught quality manual, recommends a full clean every two weeks. If any line is due, plan it before the weekend rather than after.
Sign and date the log. A daily sheet with ten numbers on it is the simplest quality system a bar can have. It also makes a strong case when you talk to a supplier about a problem keg.
Your first step: print a one page sheet with these ten checks as columns and a row for each day of the month. Stick it next to the taps and fill in tomorrow's row before you open.
Common questions
What temperature should a keg cold room be?
About 2 to 4 °C for most draught beer. Log it daily with a thermometer you trust.
How much foam should a draught beer have?
About 2 to 3 cm on a normal pour, though some styles are served with more.
How often should draught lines be cleaned?
A full chemical clean about every two weeks is the common standard.
What does a buttery taste in draught beer mean?
Often diacetyl from bacteria in a line that needs cleaning. Check the line clean log.
