The work explores the experimental and theoretical aspects of emulsification capability of ultrasound to deliver stable emulsions of sunflower oil in water and meat sausages. In order to determine optimal parameters for direct ultrasonic emulsification of food emulsions, a model was developed based on the stability of emulsion droplets in acoustic cavitation field. The study is further extended to investigate the ultrasound induced changes to the inherent properties of raw materials under the experimental conditions of sono-emulsification.

Ultrasound has been found useful in increasing the efficiency and consumer safety in food processing. Removal of heavy metal (lead, mercury, and arsenic) contamination in milk is extremely important in regions of poor ecological environment - urban areas with heavy motor traffic or well established metallurgical/cement industry. In this communication, we report on the preliminary studies on the application of low frequency (20kHz) ultrasound for heavy metal decontamination of milk without affecting its physical, chemical, and microbiological properties.

Efficient reconstitution followed by fermentation of nonfat (skimmed) dry milk is one of the most important aspects in manufacturing of various dairy products. As a first stage, dry milk is normally being reconstituted using conventional approaches such as heating and stirring the mixture. Nevertheless, we demonstrated, that low-frequency (22 ± 1.65 kHz) ultrasound can be used as an alternative to the traditional methods of milk recovery. Low-frequency ultrasound was applied during pre-fermentation stage to improve the dispersity of the resulting milk product and to create good conditions for a post-ultrasound bacterial fermentation of milk. The applied ultrasound power was set in the range of 60-120 W/L. For the fermentation process we used: kefir fungi, fermenter of direct inoculation for yogurt LYOBAC YOYO and mixed culture for kefir LAT LC K. The effectiveness of ultrasound treatment was evaluated based on the accumulation of exopolysaccharides (EPS), vitamin C content, as well as antioxidant activity of the resulting milk product. The effect of ultrasound on microflora and the role of the specific types of bacteria such as Lactobacillus on the accumulation of biologically active compounds in the fermented milk products was studied with use of electron microscopy and MALDI - to FMS method. Overall, our results showed that reconstitution of dry milk with use of ultrasound improves further accumulation of biologically active compounds and rises the nutritional quality of the fermented product.