Ultrasonic attenuation spectroscopy research for food dispersion measurement.

Abstract

Theoretical research work has been done for understanding the principle of the ultrasonic absorption in food dispersion. Four ultrasonic attenuation measurement methods have been developed. These are the through transmission method, through transmission substitution method, pulse echo substitution method, and pulse echo method. The first three methods compare echoes collected from a reference material of known ultrasonic properties with that of the sample. The last method compares reflected echoes collected from measurements on the sample only. An ultrasonic attenuation spectroscopy system for the study of ultrasonic properties of food dispersion has been developed. The results of tests on castor oil are in good agreement with the literature values. Experiments on skimmed milk, semi-skimmed milk, full fat milk, and homogenized milk’s ultrasonic attenuation spectra have been performed. The results demonstrate the effects of both fat content and fat globule particle size on the ultrasonic attenuation characteristics of milk.