Chocolate is not an emulsion.
Quoting CFR 21.163:
... chocolate is the solid or semiplastic food prepared by intimately mixing and grinding chocolate liquor with one or more optional nutritive carbohydrate sweeteners ...
Many people think that chocolate is an emulsion because one of the common ingredients is an emulsifier – lecithin.
What is Chocolate, Then?
Chocolate is a suspension of particles (most commonly non-fat cocoa solids and sugar but other particles are not ruled out) in fat (cocoa butter).
Because there is no water in chocolate it simply cannot be an emulsion, which is a mixture of a fat with water. Though an emulsifier, lecithin does not act as an emulsifier of chocolate, rather it acts to lower the surface tension between the non-fat and fat components, thereby reducing the viscosity of the melted chocolate.
Melted chocolate is also, technically, a mildly shear-thinning non-Newtonian fluid.
And now you know.
Listing image credit: Original by Rikoostenbroek on Deviant Art.
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