Fractal Analysis of Ice Crystals in Frozen Fish Meat

Abstract

Fractal analysis of shape of ice crystal particles in frozen fish meat (yellowfin tuna) was carried out by using the technique of image analysis. From a microscopic image of the ice crystal particles, it was confirmed that the perimeter of ice crystal particles could be characterized as a fractal and the fractal dimension of perimeter was evaluated. Effects of the storage time and storage temperature on the fractal dimension (d_p) of the perimeter of the ice crystal particles were also investigated. With increase of the storage time, the d_p value tended to decrease. The higher the storage temperature, the more rapidly the value of d_p decreased. The changes were in agreement with the visual observation of the shape change for the ice crystal particles reported by many researches, indicating that the fractal dimension d_p can be used as a quantitative index reflecting the surface roughness of ice crystal particles.