Engineering, Energy, Transport AIC

Elchyn ALIIEV – Doctor of Technical Sciences, Senior Researcher, Professor of the Department of Technical Systems Engineering of Dnipro State Agrarian and Economic University (St. S. Efremova, 25, Dnipro, Ukraine, 49000, e-mail: aliev@meta.ua, https://orcid.org/0000-0003-4006-8803). 
Volodymyr GOVORUKHA – Doctor of Physical and Mathematical Sciences, Professor, Head of the Department of Higher Mathematics, Physics and General Engineering Disciplines of Dnipro State Agrarian and Economic University (St. S. Efremova, 25, Dnipro, Ukraine, 49000, e-mail: hovorukha.v.b@dsau.dp.ua, https://orcid.org/0000-0002-0936-9272). 
Oleksandr PIVOVAROV – Doctor of Technical Sciences, Professor, Professor of the Department of Food Technologies of Dnipro State Agrarian and Economic University (St. S. Efremova, 25, Dnipro, Ukraine, 49000, e-mail: pivovarov.o.a@dsau.dp.ua, https://orcid.org/0000-0003-0520-171X).
Valentyn YEFIMOV – Candidate of Veterinary Sciences, Associate professor, Associate professor of the Department of Physiology, Biochemistry of Animals and Laboratory Diagnostics of Dnipro State Agrarian and Economic University (St. S. Efremova, 25, Dnipro, Ukraine, 49000, e-mail: yefimov.v.h@dsau.dp.ua, https://orcid.org/0000-0002-4286-8567).

The paper presents the results of a study on the metrological characteristics of a flow-type milk acidity analyzer designed for integration into milking equipment to enable continuous real-time monitoring of raw milk quality. The relevance of this research is driven by the needs of modern livestock farming for the implementation of digital solutions within the framework of the Smart Farming concept. Milk acidity is a key indicator reflecting the microbiological status, freshness, and suitability of milk for processing, and its timely control allows for the prompt detection of hygienic violations during milking or early signs of animal diseases.
The proposed design of the flow analyzer is based on the ionometric method for measuring pH using a glass pH-selective electrode, a reference electrode, and a DS18B20 digital temperature sensor. The measuring unit is built on an ATMega16 microcontroller, integrated with a TL082 operational amplifier, which ensures high-precision measurement of the electrode system potentials. Signal processing and measurement control are implemented via PC software, which also provides electrode calibration, acidity calculation in pH and °T units, and digital and graphical visualization of results.
To determine the metrological characteristics of the analyzer, comparative measurements were carried out using a laboratory-grade pH meter S20 (Mettler Toledo) in buffer solutions with known pH values. It was established that the electrode response is linear with a slope of 59.62 mV/pH (theoretical value – 59.16 mV/pH), the measurement range is 1.68–9.18 pH, the signal dispersion is 3.00 mV², resolution – 0.01 pH, and the signal stabilization time – up to 25 seconds. The average deviation of the results does not exceed ±0.03 pH, which confirms compliance with the requirements for operational acidity monitoring in flow conditions.
The developed analyzer is competitive in terms of key metrological parameters and has strong potential for industrial application. Further research will focus on the implementation of automatic interpretation algorithms based on processing standards, as well as adaptation of the device to farms of various scales.

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