Part of the Tools and Station school. Class 5 of 6.
The capability: you can tell a beer-clean glass from a clean one, and you know what a warm glass costs.
Prerequisites: Modules 3, 13, 32.
The practice
Run the sheeting test on twenty glasses from the current rotation. Water should sheet evenly off the interior rather than beading, per Module 32.
Run the salt test on the ones that fail.
Then pour the same beer into a beer-clean glass and a filmed one. Watch the head and the bubble trails.
Then build the same highball in a chilled and an unchilled glass and taste both at two minutes and at five, per Module 13.
And carry one across the room — because in this building the glass temperature is a working ingredient rather than a nicety.
The reference
The two glasses, side by side, with the same beer or the same drink.
What you are building
A five-second check that becomes automatic, and the knowledge of what it is checking for.
Detergent film provides nucleation sites and destroys head retention — two separate mechanisms and one test finds both.
Verification and boundary
Run the sheeting test on a random sample weekly and record the failure rate.
Boundary: glassware sanitation is governed by the local health authority.