It is 8:30 PM on a Friday. The bar is three deep. You pull a pint of lager, and it explodes into a glass full of white foam. You pour it away. You try again. Foam.

You check the gas pressure. You check the cellar temperature. You check the cooler. Everything looks fine.

So why is your beer fobbing?

Most landlords blame the equipment. But in 80% of cases, the problem isn’t mechanical. It is biological.

Your beer is fobbing because your lines have Nucleation Points caused by biofilm. And no amount of fiddling with the gas regulator will fix it.

The Fobbing Fixer

“It is biology, not mechanics.”

The Friday Night Nightmare

It is 8:30 PM. The bar is three deep. You pull a pint of lager, and it explodes into a glass full of white foam. You pour it away. You try again. Foam.

You check the gas. You check the cooler. Everything looks fine. So why is your beer fobbing?

1 Diagnose The Problem

Before you touch the gas regulator, tell us exactly what is happening:

Constant Foam

Every single pint is foam, no matter how many times I pour.

First Pint Only

The first pint is foam, but the second one pours perfectly.

The Verdict: Nucleation (Biofilm)

Most landlords blame the equipment. In 80% of cases, it is biological.

Your beer is fobbing because your lines have Nucleation Points caused by biofilm. A clean line is smooth like glass. Yours is rough, coated in dead yeast and protein. As beer hits these rough spots, CO2 breaks out, turning liquid into a missile of foam.

The Fix: The Torpedo Method

You cannot fix this with fluid. You must do it with friction.

• Step 1: Stop adjusting the gas. Turning it down causes more breakout. Keep it at 32-38 psi.
• Step 2: The Mechanical Scrub. Run a 10mm high-density sponge ball through the line. It physically scrapes off the biofilm “carcass”.

The Verdict: The 2-Degree Rule

It’s a temperature spike in the “Danger Zone”.

If the second pint is fine, your lines are warming up between pours in the 2 meters of line between your cellar cooling unit and the python exit.

The Fix: Check Recirculation

Check your water bath motor. Is the water in the python actually moving? If the bath is cold but the python is warm, your pump impeller has likely failed.

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2 The Cost of Fobbing

Fobbing isn’t just annoying; it is theft. See how much that “little bit of froth” is actually costing you.

Price per Pint (£)

£

Pints Wasted Per Week (Be honest)

You are throwing away

£2,288

PER YEAR

Investing £20 in sponge balls is the cheapest insurance policy you will ever buy.

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The Science: What is a “Nucleation Point”?

To understand fobbing, look at a champagne flute. You know how bubbles rise in a perfect stream from the bottom of the glass? That happens because the glass manufacturer etched a tiny scratch (a nucleation point) at the base. When CO2 hits a rough surface, it breaks out of the liquid and turns into gas.

Now, apply this to your beer lines.

A clean beer line is smooth like glass. The beer glides over it. A dirty beer line is rough. It is coated in Biofilm (a layer of dead yeast and protein).

• As the beer travels from the cellar to the bar, it hits millions of these microscopic rough spots.
• Each spot acts like the scratch in a champagne glass.
• The CO2 breaks out of the beer inside the line.
• By the time it hits the tap, it is no longer liquid. It is a missile of foam.

The “Fobbing Fix”: The Torpedo Method

If you have cleaned your lines this week and they are still fobbing, your cleaning fluid didn’t work. It killed the bacteria, but it left the rough “carcass” of the biofilm behind.

You need to polish the inside of the pipe smooth again. You cannot do this with fluid. You must do it with friction.

Step 1: Stop Adjusting the Gas

Turning the gas pressure down often makes it worse. If the pressure is too low, the CO2 naturally separates from the beer (breakout), creating even more foam. Put the gas back to the correct setting (usually 32-38 psi for mixed gas).

Step 2: The Mechanical Scrub

You need to run a Sponge Ball through the line.

• The Tool: A 10mm high-density sponge.
• The Action: The sponge compresses against the line walls, physically scraping off the biofilm that is causing the nucleation.

I have seen lines that were “cleaned” yesterday produce a cup full of black slime when a sponge is run through them. Once that slime is gone, the beer pours like silk.

• Get the “Fobbing Fix” Sponges Here (10mm)

Step 3: The Launch Mechanism

Remember, you cannot push a sponge through with a standard bucket. You need a pressurized system and a Cleaning Socket (Launch Chamber) to fire it.

• Get the Cleaning Socket Adapter Here

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The “False” Cause: Warmth (The 2-Degree Rule)

If you have torpedoed the lines and it is still fobbing, there is only one other likely culprit: Temperature Spike.

Beer lines are insulated (in a python), but they are not invincible.

• The Danger Zone: The 2 meters of line between your cellar cooling unit and the python exit.
• The Symptom: If the first half-pint is foam, but the second one is fine, your lines are warming up between pours.
• The Fix: Check your “Recirculation Pump” (the water bath motor). Is the water in the python actually moving? If the water bath is cold but the python is warm, your pump impeller has failed.

The Cost of Fobbing

Fobbing isn’t just annoying; it is theft. If you waste just half a pint of froth for every pint you serve during a rush, you are losing 25% of your keg.

• On an £80 keg, you just threw £20 down the drain.
• Multiply that by 52 weeks. You are losing £1,000+ per line, per year.

Investing £20 in a bag of Sponge Balls isn’t an expense. It is the cheapest insurance policy you will ever buy.

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