Cadbury's, now the world's largest confectionery group, can trace its origins in the UK back to 1824, when 22-year-old Quaker John Cadbury opened a one-man coffee and tea shop in Birmingham's Bull Street.

By 1831, John, one of ten children, had introduced a new sideline - cocoa and drinking chocolate, which he prepared himself using a mortar and pestle.

John Cadbury's lifelong involvement with the Temperance Society led him to see drinks such as coffee and cocoa as an alternative to alcohol, to which many of the social ills prevalent in society at the time were attributed.

In 1847, he moved the business to larger premises in Bridge Street, where it remained for 32 years. By 1878 the workforce had expanded to 200.

This led to the move to Bournville, Cadbury's famous "chocolate village" and the building of what is now one of the largest chocolate factories in the world.

John Cadbury retired in 1861, transferring the business to his eldest sons Richard and George.

For the two brothers, who took control aged just 25 and 21, the turning point came in 1866 when a new cocoa bean processing technique led to their new cocoa essence: "Absolutely Pure - Therefore Best."

The unadulterated Cadbury cocoa essence was lauded as a major breakthrough and, amid concerns about food additives, led to the passing of the Adulteration of Foods Acts in 1872 and 1875 and a dramatic increase in sales for the company.

By 1899, when Richard died, the Bournville factory had trebled in size and employed more than 2,600 staff. It became a limited company, with works committee, medical department, pension funds and education and training for employees.

The Bournville factory became a "series of factories within a factory". Everything was produced on site, with tin box pressing plants, carton making units, a design studio and printing plant.

This continued until after World War II, when the Cadbury business was "rationalised" into a producer of chocolate confectionery and began to use external suppliers for the first time.

Now, the 60-acre site at Bournville employs about 3,000 people, producing chocolate bars such as Cadbury Dairy Milk and Fruit & Nut at one site, while the "assortments factory" makes Milk Tray, Roses and Easter Eggs.

Each week the Bournville site alone produces in excess of 1,800 tonnes of chocolate, according to Cadbury .

The Somerdale factory near Bristol, which employs around 750 people, produces lines such as Double Decker, Crunchie and Fry's Turkish Delight.

At Chirk in North Wales, the group says it has one of the world's most modern cocoa processing plants employing around 200 employees and processing about 50,000 tonnes of cocoa beans a year.

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