Modelling temperature distributions in cooling chocolate moulds

The moulding of chocolate is technically challenging, and is dependent on the solidification of the constituent cocoa fats into the correct polymorphic form (Form V). This gives a product which is attractive to the consumer as well as possessing good demoulding and bloom resistance properties. Form V is produced following a tempering process involving a complex temperature profile in which seed crystals are produced. However, other polymorphs can nucleate and grow during moulding if the cooling rate is excessive. A computational model has thus been developed to predict the temperature in the mould as a function of space and time. The model uses enthalpy-temperature data obtained over a range of cooling rates. It has been validated using thermocouple data taken from a model mould during air cooling over commercially relevant conditions. (C) 2000 Published by Elsevier Science Ltd. All rights reserved.