I haven't drunk ordinary Guinness for a long time, but Foreign Extra Stout definitely has a sour tang to my taste buds. Wikipedia says that "Guinness Flavour Extract, a dehydrated, hopped wort extract made from barley malt and roasted barley, is used for overseas production of the stout. The syrup is shipped from Ireland, where it is added at the ratio of 1:49 to locally brewed pale beer. In most overseas markets, Guinness Flavour Extract (GFE) is blended with locally brewed beer to produce FES.". So how about getting a bottle of Foreign Extra Stout and adding it to your homebrewed stout?
(Incidentally, in the Caribbean I've drunk Guinness brewed in Ireland and immediately afterward Guinness made under license in St Vincent - definitely different in taste. And Nigerian Guinness has sorghum listed as an ingredient! Different taste again.)
(Incidentally, in the Caribbean I've drunk Guinness brewed in Ireland and immediately afterward Guinness made under license in St Vincent - definitely different in taste. And Nigerian Guinness has sorghum listed as an ingredient! Different taste again.)
