Electrorheology is the study of the effects of electric fields on the
flow properties of fluids. These materials generally exhibit an increa
se in apparent viscosity and a greater yield stress over an unelectrif
ied sample. The phenomenon requires an electric field and polar partic
les suspended in an insulating oil. A standard concentric cylinder vis
cometer, fitted with custom made electrical attachments, was converted
into an electrorheometer. This system allowed control of DC voltage (
0-450 Volts mm(-1),) fluid temperature (35C-40.5C), and shear rate (0.
022 s(-1) - 8.744 s(-1)) while observing the resulting effects on the
shear stress. Dimensional analysis was used to study the rheological r
esponse of milk chocolate when subjected to electric fields. Dimension
less groups were identified to explain the phenomena, and multiple reg
ression analysis was used to predict the electrorheological flow behav
ior of milk chocolate. Over the ranges of input variables, the electri
c field-induced forces dominated the rheological response over thermal
forces, and a prediction equation for apparent viscosity was develope
d as a function of electric field strength and shear rate. This mathem
atical expression allows for prediction of milk chocolate rheology in
the presence of an electric field.