The effect of ultrasound on the functionality and health-improving properties of dairy products (review)

Abstract New technologies used in the food industry are aimed at producing minimally processed products that are healthy and safe. The aim of this work was to study the influence of ultrasound on the functional and health properties of milk and dairy products, to examine specific mechanisms by which ultrasound changes the properties of dairy products, and to compare it with traditional and new technologies for processing dairy products. Milk β-lactoglobulin does not change its modification during low-temperature pasteurization, however, during high-temperature pasteurization, its hydrolysis in the stomach increases, while a decrease in calcium binding is found. It has been established that milk homogenization using ultrasound is useful for the inactivation of bacteriophages. Of particular interest is high intensity ultrasound, which has great potential for monitoring dairy products. It has been established that ultrasound is used as a quite gentle method (short-term exposure) to control the coagulation and gelation process in milk protein suspensions, reconstituted milk, and fresh milk. Many studies linking texture and rheological properties with acoustic properties have been conducted on cheeses during coagulation and fermentation processes. Under the influence of ultrasound, three stages are distinguished during milk coagulation caused by the action of rennet enzyme: at the first stage (pH > 5.1, without changing rheological parameters), aggregation or gel formation does not occur, at the second stage (4.85 < pH < 5.1, G" frequency increases and pH decreases), aggregation begins, and at the third stage (pH < 4.85, G' and G" increase rapidly with pH, which leads to the formation of a three-dimensional gel network of casein particles in milk), gel is formed in full. However, there are currently many limitations and conflicting results regarding the effects of ultrasound on dairy products. Additional research will provide a complete picture of how ultrasound exposure affects the characteristics of biologically active components of functional dairy products. Graphical Abstract