Basically, the sonication of food staff by sufficient intensity and low frequency causes the death of living cells of plants, animals, microorganisms and enzymes which are active. At the same time, this method prevents of damaging the nutrients and producing of harmful substances due to applying low temperature for processing. On the other hand, diagnostic ultrasound with low intensity and high frequency, are not detrimental in many division of the food industry so it has other applications such as determining: the thickness of the material, the amount of foreign material, food temperature, flow speed of material, the size of the particles, the stability of the colloidal dispersion, the changes of food phases, gelation, molecular characteristics of foods.