SUMMARY
The purpose of the research is to create an optical piezometer and a working chamber of a high-pressure apparatus for spectral studies of food products (liquid and viscous plastic) in situ; to obtain indicators of compression and spectral (optical) properties of food products of animal and plant origin with precision at pressures from 0 to 1000 MPa. Methods. The developed optical piezometer is based on the Michelson principle of interferometer. Changes in the volume of the studied food samples under pressure are recorded when the concentrically located interference rings from the laser module change. The precision of pressure recording is provided by measuring the change in the position of a more intense R2, the line of the luminescence spectrum of a ruby located in the working chamber, when the pressure changes. Result. For the first time, the design of the high-pressure working chamber allows obtaining in situ experimental data on changes in the compressive parameters (absolute and relative volume, density, volume modulus of compression, isothermal compression coefficient) of solid, viscoplastic and liquid food products with precision. The accuracy of measuring the change in the volume of the studied samples is not less than 0.0003 mm3. To obtain the spectral characteristics of food products in situ, the windows of the working chamber are composed of NaCl, a ruby crystal, and protective plates made of sapphire crystals. The test sample is in a developed hydrostatic cuvette installed in a high-pressure chamber and consisting of a fluoroplastic glass, sodium chloride plates and a ruby plate 0.5 mm thick. Conclusions. The research results allow us to reasonably develop high-pressure food processing technologies and design the appropriate technological equipment.