Charles Wells, the Bedford regional brewer, is launching a five-litre "mini cask" of real ale that is going on trial at £11.99 a time, £1.36 a pint, in five Asda supermarkets around the country from Leicestershire to Kent.

The mini cask, filled with Wells's Bombardier bitter, has received the enthusiastic support of the Campaign for Real Ale (Camra), which is letting the brewer use Camra's own "Ask If It's Cask" logo, which promotes the choice of and preference for cask ale, on the packaging.

All consumers have to do is keep the mini cask in a cool place, a garage, fridge or pantry are ideal storage environments. Then allow the mini cask to stand undisturbed for three to four hours to settle. Then they tear off the foil on the tap off the side and pull the tap out. Refrigerated or stored in a cool area, the mini cask will keep for up to 10 days.

Charles Wells's commercial director, Nigel McNally, said: "By comparing the share of cask beer in the on trade we estimate that fresh real ale in the take home sector is a £250m market opportunity at retail value. Our research confirms that over 80% of consumers who try fresh real ale will repeat purchase rather than buy long life beer."

The mini casks are made from steel and supplied by Datagraf of Germany. The casks are then filled at the Bedford brewery.