Glass firm puts more fizz into drink: The 'just poured' frothy head on lager lasts longer thanks to a coating technique just developed

DRINKERS will be sure to keep their heads if they use a specially adapted glass that keeps lager fizzing for longer.

Charles Glassware, which puts the logos and badges on finished glass for British breweries (including Carlsberg- Tetley, Whitbread and Guinness) has developed a way of controlling 'nucleation'. This is the process in which dissolved carbon dioxide is released as bubbles, giving lager its fizz and creating the head.

The company has applied for a patent for the process, which it says will help lager to keep its head and bubbles for up to an hour after being poured. Clive Waugh, the managing director, says: 'Brewers have been pestering me for years to come up with a way of improving the appearance of their product by maintaining the just-poured appearance of lager. Typically, lager dispensed into standard beer glasses loses its head very quickly, and soon after the bubbles all but disappear.'

The company's process involves treating finished glasses with glass particles fired to a temperature of 580C in a machine designed by Mr Waugh and manufactured for the company. This softens the glass, fixing the particles before they become molten. The particles, which can be in the form of company or brand logos, create nucleation sites around which the bubbles of carbon dioxide form. Mr Waugh says that the process of nucleation is not completely understood but it has long been known that roughening the surface of a glass makes its contents fizzier.

'The saucer glasses supplied for the original Babycham had a cross scored on the inside to give the drink its sparkle.'

It is also well known to many who wash dishes that champagne fizzes more if the glasses have not been cleaned properly. Tests have shown that adding the glass particles has no effect on the life of the glass, unlike other methods of roughening the glass such as sand- blasting and laser engraving. By varying the number of glass particles, the amount of carbon dioxide that is given off can be controlled exactly.

Releasing the carbon dioxide while the lager is in the glass will also make it easier to drink, since the gas will no longer be released in the stomach.

Charles Glassware's first contract for fizzy glasses comes not from a lager brewer but from Taunton Cider. The technique will also work on keg beers, but not on carbonated soft drinks.

(Photograph omitted)