Fast conching for milk chocolate

Abstract

The objective of the study was to shorten the conventional conching process for milk chocolate, which still takes many hours, in order to increase productivity. Due to recent findings and to progress made in raw material treatment, a hypothesis was proposed: that flavour development in the conch could be less important for milk chocolate than it certainly is for dark chocolate. Other functions of conching, like water removal and fat covering of particles, could be achieved faster by using drier raw materials and by machines applying more shear force. For the experiments, a conventional process (taking 5 hours) was condensed into 30–90 minutes. In screening trials various flake pre-drying techniques were also tested. Samples produced were analysed for particle size and flow properties, as well as by a trained sensory panel. Results from the experimental design showed best results at 60–90 minutes conching time. Probably the procedures for flake pre-drying had little or no influence under the conditions used. Verification trials compared the fast conching procedure to the standard process using two different recipes. No relevant differences in physical or sensory properties were found between samples from standard and 90-minute-fast-conching, proving that under favourable conditions conching times for milk chocolates can be drastically reduced without negative impact on product properties and perception.