Research into short-measures being served in pubs across the UK may help the trade persuade ministers against bringing in a compulsory 100 per cent liquid pint.
A National Beer Dispense Database, giving exact measurements of the amount of liquid in each pint served, is currently being compiled.
The move follows concern among licensees over proposals from the Department of Trade and Industry (DTI) that would force them to serve an average of 100 per cent liquid.
The DTI claims its own research found as many as eight out of 10 pubs are serving short measures.
Now The Publican Newspaper has learned that one of the UK's top pub operators, which has yet to be named, is trialling a new system called Head Miser which calculates the exact percentage of liquid in every pint served and feeds the figures through to a central computer so that they can be compared by region, product or type of pub.
The manufacturers of the equipment, Linburn Technology in Dunfermline, claim the results of the trial can be used by the trade to support its argument for self-regulation.
Managing director of Linburn Jim Mitchinson said: "It is not necessarily about the quantity of beer in the glass, many consumers like a head, but about the consistency.
"Pubs can monitor that to improve the consistency and while it will cost them a little more in extra beer, that is less than it would cost if the government legislated."
It has been estimated that a change in the law could hit the trade hard, forcing licensees to introduce oversized glasses for customers who like a head on their beer, and costing millions every year through accidental overfilling.