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Homogenization is a necessary process in the production of drinking milk and most dairy products. The specific energy consumption of the most common valve homogenizers reaches 8 kW h.t-1. A promising way to reduce it is the introduction of more effective counter-jet homogenizers. The purpose of these studies is to increase the efficiency of machines of this type through fuller use of their kinetic energy. To achieve this, the design of a ring reflector was developed and experimental studies were carried out to determine its influence on the efficiency of milk fat dispersion in a counter-jet homogenizer. Calculations were made to determine the reflector’s design parameters. An installation for experimental research has been developed, in which the required milk pressure is created with the help of compressed carbon dioxide. The dispersive indices of the milk emulsion were determined by computer analysis of milk sample micrographs obtained with an optical microscope and a digital camera using Microsoft Office Excel and Microsoft Visual Studio C# software using the OpenCV Sharp library. As a result of research, the formula for defining the angle of the reflector top has been determined analytically. Experimental studies proved its validity and allowed determination of the optimal diameter. A comparison of the dependence of the degree of homogenization on the excess pressure in a counter-jet homogenizer proves a 15 – 20% increase in the degree of dispersion when using a reflector. At the same time, specific energy consumption does not increase. Comparison of the distribution curves of milk fat globules by size after counter-jet homogenization and homogenization with a reflector suggests that the average diameter of fat globules for the experimental method decreases from 0.99 to 0.83 μm. This indicates the high quality of the dispersal characteristics of the milk emulsion after processing in a counter-jet homogenizer with a reflector.

The modification of rotor-pulsation machine – pulsation machine with a vibrating rotor (PM with VR) has been researched in the work. Rotor in such modification not only rotates but also oscillates axially with the frequency about 3000 min-1 and amplitude 0,5–1,0 mm. The aim of this research was to define specific features of milk homogenization process in PM with VR and disperse characteristics of milk emulsion. Analytical researches resulted in finding dependence of milk emulsion acceleration as a main factor of milk fat particles breakup subject to the design and kinematic parameters of PM with VR. Experimental researches were carried out on the laboratory setup of the pulsation machine with a vibrating rotor which was designed by the authors. The subject of experimental researches is cow's milk. The sizes of milk fat globules after homogenization were measured by the optical microscope equipped with a digital camera. The researches resulted in defining characteristics of milk emulsion dispersing in PM with VR. Thus acceleration grows when diameter, oscillation amplitude and rotation frequency of the rotor are increased, and channels length of the rotor and stator, the gap between them are decreased and the number of rotor openings is 4 or less. Empirical dependence between the average diameter of the fat globule (0,7–1,9 μm) and the average emulsion acceleration ((1–10)·103 m/s2) in the interrupter of PM with VR is defined which proves that the emulsion flow acceleration is the main cause of homogenization of PM with VR with 92 % confidence. High quality of the milk emulsion after processing in PM with VR has been proved. The crankshaft rotation frequencies up to 2880 rpm and rotor oscillation amplitude of 1 mm enable to receive milk emulsion with the average dispersion about 0,8 μm that corroborates using PM with VR in the industrial conditions for milk homogenization to be perspective.

The study of technological parameters of Midas wheat flour and possibility to use little-spread plants at wheat bread manufacturing was realized. Parameters and regimes for keeping and baking bread of new recipes were elaborated and selected. The elaborated method of bread manufacturing by new recipes relates to the field of agriculture and food industry and may be used at a laboratory baking of bread. There was experimentally grounded and introduced the change of a part of recipe quantity of wheat flour for dried and comminuted plants of Népeta mussinii L., Polymnia osotolysta L., Amaranthus tricolor L., Cosmos sulphureus L., Tanacetum parthenium L., Cyperus esculentus L., Physalis tomentous L. at baking bread. According to determined physical-chemical, organoleptic parameters of bread, a possibility of baking bread using plants was proved. The expedience of introducing vegetable additives of Népeta mussinii L., Polymnia osotolysta L., Amaranthus tricolor L., Tanacetum parthenium into wheat dough in the dose no more than 5 % to the flour mass; up to 10 % – Cosmos sulphureus L and up to 15 % – Cyperus esculentus L., Physalis tomentous L was proved. At these very dosages bread had an evenly colored crust, without breaks and cracks, elastic crumb, thin-walled porosity, expressed bread taste and pleasant smell of additives as opposite to other experimental samples.

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Kovalyov a., samoichuk K., Palyanychka n., Verkholantseva V., yanakov V.