CONTROL OF FAT CONTENT OF FEED CAKES BY LUMINESCENT METHOD

The increase in livestock productivity and quality indicators is associated with an increase in the nutritional value of feed. The control of nutritional value parameters is a key aspect related to the optimization of feeding rations, increasing the productivity of animals, their development and health. An alternative to traditional chemical methods of analysis are optical spectral methods of feed analysis. These methods are characterized by high accuracy, non-invasiveness, and speed of analysis. (Research purpose) The research purpose is applying a luminescent method of controlling the fat content in sunflower and soybean cake to create a technique for photoluminescent diagnostics of the fat content of cake. (Materials and methods) Measurements of spectral characteristics and calculations of integral and statistical parameters of sunflower and soybean cake were carried out using a diffraction spectrofluorimeter CM 2203. A control measurement of the fat content was performed using the FOSS NIRS DS2500 device. (Results and discussion) It was shown that the synchronous excitation spectra of sunflower and soybean cake contain two main maxima characteristic of plant feeds - 362 nanometers and 424 nanometers. It was determined that with an increase in the fat content in the cake, quantitative changes in the spectra are noticeable - a decrease in luminescent ability caused by quenching luminescence. It was found that all spectra have right-sided asymmetry and are island-like. It was found that the photoluminescent properties of soybean cake are much better than sunflower cake: the flux value for soybean cake at λb = 362 nanometers is 3.6-4.3 times higher than the flux for sunflower cake, at λb = 424 nanometers - 18.7-19.9 times; the excitation statistical parameters do not change systematically when the fat content changes. (Conclusions) It was found out that photoluminescent control of the fat content in feed cakes can be carried out along the photoluminescence stream, since statistically reliable linear dependences of fluxes on fat content with determination coefficients of 0.89-0.99 were obtained with a relative error in determining fluxes of no more than 4-7 percent. It was noted that the obtained dependencies can be used in the development of methods and devices for feed quality control.