Abstract
The optical properties of meadow and alfalfa hay of various fractions and classes were studied. The purpose of the research was to identify the quality hay class by optical properties in photoluminescent identification. The spectral characteristics of excitation and luminescence were obtained using a CM2203 spectrofluorometer. Excitation spectra in the wavelength range of 230–600 nm and photoluminescence spectra at excitation of 362 nm, 424 nm, 684 nm were measured. The integrated absorption capacity and photoluminescence fluxes, as well as statistical parameters were calculated. All spectra had right-sided asymmetry, with the exception of alfalfa hay, and pronounced flatness. It has been established that alfalfa hay vibrates more strongly at 684 nm than meadow hay, and vice versa at 424 nm. The difference in the integral photoluminescence fluxes for different types of hay is 1.5–3.9 times, for different quality classes – 3.7–19.3 times. As a result of the research, informative excitation wavelengths were revealed to identify the grade of hay. A method for determining the amount of 1st class hay in meadow mixed-grass hay can be implemented through the analysis of the flow ratio Φ362 /Φ424, and a method for the objective identification of higher-protein alfalfa hay – by analyzing the flow ratio Φ362 /Φ424. The value of the results obtained lies in the formation of a theoretical basis for the production of analytical instruments used in agriculture for the diagnosis of feed on a cheaper and small electronic component base. The hardware implementation can be carried out using monochrome LEDs as radiation sources, and photodiodes as radiation receivers.