Thermo-mechanical method for the determination of the fractal dimension of fat crystal networks

Abstract

The physical properties of a fat are determined by its thermal history, processing conditions, chemical composition, polymorphism and spatial distribution of mass. The mass fractal dimension of a fat crystal network can be determined from the slope of the log–log plot of the storage modulus (G′) versus the solid fat content (SFC). Different SFCs were obtained by melting the fat, diluting it to different extents in liquid oil, and crystallizing the blends under specific conditions. One of the major drawbacks of this method is the inability of characterizing the native structure of an already crystallized fat. In the thermo-mechanical method developed in this study, SFC is changed via temperature variations instead. At each temperature, the G′ and SFC were measured and the fractal dimension calculated as described above. The thermomechanical method proved to be a simpler and more reliable estimator of the fractal dimension of a fat crystal network than the dilution method.