Bitters developed towards the end of the 19th century as brewers began to produce beers that could be served in pubs after only a few days storage in cellars. Bitters grew out of pale ale but were usually deep bronze to copper in colour due to the use of slightly darker crystal malts.
Towards the end of the 19th century, brewers built large estates of tied pubs. They moved away from vatted beers stored for many months and developed ‘running beers’ that could be served after a few days’ storage in pub cellars. Draught Mild was a ‘running beer’ along with a new type that was dubbed Bitter by drinkers. Bitter grew out of Pale Ale but was generally deep bronze to copper in colour due to the use of slightly darker malts such as crystal that give the beer fullness of palate. Best is a stronger version of Bitter but there is considerable crossover.
Bitter falls into the 3.4% to 3.9% band, with Best Bitter 4% upwards but a number of brewers label their ordinary Bitters ‘Best’. A further development of Bitter comes in the shape of Extra or Special Strong Bitters of 5% or more: familiar examples of this style include Fuller’s ESB and Greene King Abbot.
With ordinary Bitter, look for a spicy, peppery and grassy hop character, a powerful bitterness, tangy fruit and juicy and nutty malt. With Best and Strong Bitters, malt and fruit character will tend to dominate but hop aroma and bitterness are still crucial to the style, often achieved by ‘late hopping’ in the brewery or adding hops to casks as they leave for pubs.Information from www.camra.org.uk/page.php?id=228