The directors of the Marmite Food Extract Company took only two years to persuade a nation of marmalade lovers that their black gold was just the thing for toast. Nearly a century later the thick, tar-coloured paste with a salty taste is extracting pound;23 million a year from the pockets of UK shoppers, and a pot of the stuff lingers in the larder of a quarter of all homes.
The Marmite story really begins back in 1680 when a Dutch scientist called Leouwenhoek first studied the spherical cells of spent brewer's yeast under a microscope. Years later Louis Pasteur realised that the cells Leouwenhoek had seen were those of a living plant. Until then, everyone had assumed that the effort of turning sugar into alcohol killed the yeast. The holy grail of yeast extraction then passed to a German chemist called Leibig who succeeded in producing a concentrated paste.
By 1907 Marmite's direcors had done so well out of old yeast that they opened a second factory in south London. They received a further boost in 1912 with the discovery of vitamins. The company realised that the nation's favourite vegetarian spread happened to contain five B vitamins, and soon Marmite was being promoted as a healthy food. Babies were fed Marmite soldiers, as were real soldiers. During the First World War, it was shipped out to troops in Mesopotamia to combat beri-beri.
So what's in the name? One theory is that it was inspired by the dark juices produced in a "marmite", a French, double-handled, earthenware casserole used for stews and soups. The word is said to derive from the Old French for hypocrite - it is a pot that hides its contents. A picture of said receptacle still adorns the label today.
Marmite was itself sold in small earthenware pots until the 1920s when the decision was made to switch to glass jars with metal lids. Fifty years on, the company dropped another bombshell: the metal lid was to be replaced with a plastic one. Rumour has it that some ageing Marmite babies could not cope and stockpiled the old jars and lids. Now, where did I put mine...?