Chocolate typically contains up to 40% fat by volume and is composed of cocoa, sugar, milk solids, and other particles suspended in liquid fat, such as cocoa butter. Reducing chocolate’s fat content increases the liquid’s viscosity and clogs production pipelines. Hence, manufacturers have largely failed in attempts to create low-fat chocolate.

Nowresearchers developed a method in which an electric field applied along the flow direction of liquid chocolate causes solid cocoa particles to clump into short chains and spheroids in a streamlined manner.

Because particle shape influences intrinsic viscosity, the authors reasoned that the electric field-induced clumping would break the particles’ rotational symmetry and reduce both the suspension’s viscosity and the minimum amount of melted fat required to maintain proper texture and flow within the pipeline.

Application of an electric field of 1,600 V/cm reduced the viscosity of a sample of Mars chocolate by 43.5%, enabling a potential reduction in fat content greater than 10%. Similar results were obtained with samples from other manufacturers, suggesting the method’s wide applicability. With further improvements, such as optimizing the strength and duration of the electric field, the method might help pave a long-sought path toward the manufacture of low-fat chocolate, according to the authors.

http://www.pnas.org/content/early/2016/06/16/1605416113