To study the spectral characteristics of melamine to assess the safety of milk and its processed products during laboratory control

Abstract

Existing methods for the determination of melamine in milk and its processed products are time-consuming to reproduce, require special equipment, training of personnel to work on this equipment, the use of chemical reagents and auxiliary equipment, often expensive. A separate area in the analysis of food products is spectroscopy in the middle infrared range, used to identify substances. The aim of the work was to record and analyze the infrared spectra of a standard sample of melamine in the middle spectral range using an NSAID prefix, a collapsible liquid cuvette and vaseline, as well as in tablets with KBr. The research was carried out in stages on the basis of the educational and research center for the examination of food and Animal Feed of the St. Petersburg State University of Veterinary Medicine in 2024. A standard sample of melamine was used as the research materials. At the first stage, the spectra of a standard sample of melamine were recorded using an infrared Fourier spectrometer "InfraLUM FT-08" and an NPVO prefix with a ZnSe crystal. At the next stage, the spectra of a standard sample of melamine in petroleum jelly were taken using a collapsible liquid cuvette, and then melamine pressed into tablets with KBr. As a result of the conducted studies, the presence of absorption bands of varying degrees of intensity in the IR spectra of the standard melamine sample was established, characterizing various types of fluctuations in the bonds of NH and CH groups. When comparing the IR spectra of melamine obtained at different stages of the study, a decrease in the intensity of the recorded absorption bands in different regions of the middle spectral range was revealed when using a liquid cuvette with vaseline and tablets with KBr. In addition, it was found that the IR spectrum of melamine obtained using the NSAID prefix exceeded the intensity of the absorption bands of similar spectra taken using KBr tablets and a liquid cuvette with vaseline.