Moulding of chocolate has been used to make sweets since the nineteenth century. Initially it was carried out entirely by hand, but over the intervening years, automation has gradually taken over. Early moulding lines stillrequired a lot of people to move the moulds from one stage to the next and to carry out operations such as inversion of moulds, topping up depositor hoppers, and even scraping off excess chocolate from the moulds. Further automation was gradually introduced until, during the last quarter of the twentieth century, advances in electronics and automation techniques allowed the number of operators to be reduced to one per plant, and sometimes even one between two plants.
At the same time, the metal moulds which were originally used, have
been replaced by plastic, normally polycarbonate ones, resulting in a significant reduction in noise in the production areas. The easier handling of these lighter moulds has allowed the introduction of automatic mould changers, both for complete changes of moulds and for the removal of individual moulds, which have undemoulded items left in them. Polycarbonate moulds are also more flexible, so they can be twisted to aid demoulding.
Plant speeds have increased from just a few moulds per minute (mpm) to
around 70mpm for solid items, and plant widths from 275mm to 1800mm
(12–75in.) are now available with capacities of up to 10000kg/h (10ton/h).
This has all meant that outputs have steadily increased, whereas labour
requirements have fallen. In general, reliability has also improved, though
some of the earlier automated lines in particular, continue to give problems unless heavily modified.
Other recent improvements include easier cleaning and attention to hygiene; with construction methods using solid supports to eliminate hollow bodies, components being installed with a clearance to the floor to allow easy inspection and cleaning underneath, and electric cables being routed away from dirty areas or made easily accessible for cleaning. Wood and plastic cladding have been replaced by clear polycarbonate so that all the components are visible, and leaks and spills can be seen and eliminated.
