Positron annihilation study of structural relaxation and crystallization of glassified milk fat

Kinetics of the milk-fat phase tran- sformations and the features of its defect structure in amor- phous, crystalline and liquid states were studied using the positron annihilation technique. The highest concentration of the free-volume type defects with the average radius of 0.36 nm was found for the amorphous state and the lowest concentration for the crystalline one. It is shown that glassified milk fat can be transformed to the liquid state (bypassing crystallization stage) upon rapid heating.