Back to Applications      Back to Cryo-SEM Library

Ice Cream

Despite starting as a liquid, ice cream is a solidified foamed emulsion containing air as the primary disperse phase. The air content of ice cream varies between products but is generally about 50%, with a total fat content of 10 -12%.

At low magnification air bubbles of a variety of diameters are visible dispersed amongst a frozen emulsion. The ice crystal diameter is between about 5 and 10um.

At higher magnifications fat globules (small arrows) of a variety of sizes (between 200nm and 2um) are visible both at the gas/ice surface and also in the eutectic boundary between ice crystals. In addition, large angular lactose crystals are visible (larger arrows).

The texture and rheological properties of ice cream are directly related to structure, and in particular;
a. the percentage and dispersion of fat,
b. the ice crystal size and,
c. the size of air bubbles.

Etching (sublimation) shows the ice crystal spaces

Deep etched (sublimated) ice cream preparation