­An experimental installation for LED ultraviolet (UV) disinfection of raw milk in a Couette – Taylor reactor has been developed. The results of modeling the distribution of irradiance on the inner surface of a quartz tube as a function of the distance between a printed circuit board with UV LEDs and a quartz tube are presented. An important parameter of the UV milk treatment system is the residence time of the elementary milk particles in the surface layer of the reactor. To evaluate it, the trajectories of individual milk particles were modeled and their radius vector (depth of immersion) was calculated in the cylindrical coordinate system of the UV reactor. In the course of the research, a series of experiments was conducted to study the effect of the rotor rotation speed inside the reactor and the intensity of the UV LEDs on the effectiveness of milk disinfection. An analysis of the results shows that both rotor speed and UV LED power have a strong effect on the effectiveness of reducing the number of mesophilic aerobic and facultative anaerobic microorganisms (NMAFAnM). It was shown that when milk was disinfected using the installation under an optimal treatment regime, the content of NMAFAnM in a cow’s milk sample decreased 21-fold, and the coliform bacteria (BECG) count decreased 16-fold, which meets the requirements for drinking milk. The results obtained can be used in the design of energy-efficient industrial installations for UV disinfection of milk.

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