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Butter

Butter is a complex colloidal system which is manufactured by churning dairy cream. The cream, which is an emulsion, is foamed and the emulsifiers - mainly protein -become desorbed and spread out onto the surface of the air bubbles. The fat droplets thereby lose their stability and coalesce into much larger drops.
Continued foaming brings about the collapse of the foam structure. Further churning results in the distribution of water (dispersion phase) throughout the fat (continuous phase). On average, butter contains about 82% fat. In the micrograph, water can be seen as both amorphous shaped ice crystals (1) and spherical droplets (arrows). In places, air bubbles are still obvious (a).

Bar = 10um.