Andrew Broadbent, Project Engineering Manager and Colin Harper, Cadbury Process Engineer hosted the visit, ably assisted by the Cadbury team of Tour Guides.

On opening the proceedings Colin Harper gave us a very informative presentation on the history of Cadbury and techniques in Chocolate manufacturing.

The site history gives an insight into industrial and social development, covering well over a century and a half to present day. Colin explained how a one-man business, opened in 1824 by a young Quaker, John Cadbury, in Bull Street Birmingham, was to be the foundation of Cadbury Limited. By 1831 the business had changed from a grocery shop and John Cadbury had become a manufacturer of drinking chocolate and cocoa, the start of the Cadbury manufacturing business, as it is known today.

During 1878, and after expanding the workforce to 200, the business moved to a Green field site at Bournville where there was a good water supply access to a canal and plenty of space. There was also the opportunity improve the working conditions and sports and leisure centres were built as well as dining halls and medical centres. As part of this development a new village and school was built on the green fields of Kings Norton.

After hearing this fascinating story Colin went on to explain the integrities of Chocolate making. Production starts at the Chirk cocoa factory, situated near Wrexham, where the highest quality cocoa beans are processed to produce cocoa ‘mass’ containing 55% cocoa butter plus extracted cocoa butter, the basis for all chocolate products. When plain chocolate is made the ‘mass’ goes straight to the Bournville factory in Birmingham while the ‘mass’ for milk chocolate production is taken to the Cadbury milk factory at Marlbrook, Herefordshire, in the heart of English dairy country.

At the milk processing factory fresh liquid full cream milk is cooked with sugar and condensed to a thick liquid. Cocoa mass is added, making a rich creamy chocolate liquid, which is then evaporated to make milk chocolate ‘crumb’. As these ingredients are cooked together the very special rich creamy taste of Cadbury chocolate is produced.

Over 95,000 tonnes of ‘crumb’ a year are produced at Marlbrook to be made into chocolate at the Cadbury chocolate factories at Bournville, Birmingham and Somerdale, Bristol.

On arrival at Bournville for the final production stages the ‘crumb’ is pulverised by heavy rollers and mixed with additional cocoa butter and special chocolate flavourings. The amount of cocoa butter added depends on the consistency of the chocolate required: thick chocolate is needed for moulded bars, while a thinner consistency is used for assortments and covered bars.

The most important component of chocolate, as far as texture is concerned, is the fat, and the special processes known as ‘conching’ and ‘tempering’ are very carefully controlled to produce chocolate with the fat in a specific physical structure. The fat must coat individual particles of cocoa, milk and sugar, combining them together to form the solid chocolate. ‘Conching’ involves mixing and beating the semi-liquid mixture to develop the flavour, removing unwanted volatile flavours and reducing the viscosity and particle size.

‘Tempering’ is the final crucial stage. It is a complex process, which in simple terms involves mixing and cooling the liquid chocolate under carefully controlled conditions to ensure that the fat in the chocolate crystallises in its most stable form. Highly sophisticated machinery has been developed for this process and the control of it is one of the skills of the Chocolatier.

Since the late 70’s a great deal of Capital has been invested at Bournville to modernise the Wet End processes, an initial investment of £100m, and more recently on Dry End Packaging to meet the current production figure of 120.000 tonnes of chocolate p.a. including 10m Crème eggs. The site now employs 900 people in the manufacturing plant.

The innovative methods of the Chocolatier were clearly visible during our tour of the Factory. As well as the production line for Crème eggs we were able to see the Easter egg production line with its pouring and moulding machines where vibration is a critical part of the process. The moulded eggs were being orientated by a machine that picked and placed half eggs into a half mould whilst picking and placing the top half at the same time at high speed. Aluminium foiling machines are used to hold the eggs in one piece for check weighing and final packing processes.

The production lines for the Heroes Brand were also very impressive with the mixture being fed into a layering plant to form a slab of the centre. This was then slit into rows, which were then cut by an ultrasonic guillotine to the correct length. The centres then past down the line into an enrober to be covered with chocolate. After wrapping individually, at a speed of 500 items/min, batches of chocolates are metered and fed into Cartons via check weighers. This operation was on a large scale.

All products are despatched in boxes that were palletised on robotic machines programmed to place each box to a predetermined stacking pattern before being transported to refrigerated, off site warehousing.

Over a buffet lunch John Yates BBI National Chairman thanked Andrew Broadbent and his Colleagues for an excellent visit, an informative presentation, and comprehensive tour of the plant, and congratulated Andrew on the high standard of the Factory.

From our visit it was evident that the Cadbury guiding principles of Quality, Cost, Delivery, Safety and Morale were well established, and good reasons for Cadbury recently being awarded the winning title of ‘Britain’s Most Admired Company’.

Brian Gibbs BBI Southern Section Coordinator