The main operations of the process of producing multicomponent mixtures are dosing and mixing operations. The technology of vegetable protein production from sugar beet processing wastes involves the process of dosing and mixing organic acid solution with squeezed juice. The optimal selection of process equipment has an impact on the quality of the obtained product. These processes can be carried out using a liquid batcher mixer. The analysis of the design features of the existing batcher mixers showed their main disadvantages. There are the nonuniformity in the distribution of the additional liquid in the main liquid flow, the additional energy costs for driving the mixing element and the low degree of homogeneity of the finished mixture. An experimental plant for conducting researches of a batcher mixer has been developed. Analysis of the functioning of the used equipment was carried out to determine the main parameters of the liquid dosing and mixing processes. The design diagram of measuring instruments arrangement at the experimental assembly is presented. The purpose of the research in the liquid batcher mixer was to determine the dependencies of qualitative indicators of the obtained mixture on the design parameters. Functions of uniformity of distribution of solution of organic acids in juice on the design parameters of the batcher mixer are shown. Dependencies of coagulation time and the amount of the obtained protein on the content of organic acid solution are presented. Experimental researches made it possible to substantiate the optimal design and technological parameters of the batcher mixer.