Only pint served in the survey contained a full pint of liquid.

Officers visited a number of pubs and found on average drinkers were getting 5% less beer in their glass than they should be - 10p in monetary terms.

Only one pint served in the survey was a full pint and several premises are being warned about the issue.

Officers say it now opens up the debate about whether froth should be included.

They say the problem is that many pubs have only brim pint glasses which means to get a full pint of liquid in, drinkers would get no head on their pints.

The survey also discovered the average price of a pint in local pubs was �2.07, and the average price of a pint of lager was �2.18.