ШЛЯХИ ВИЗНАЧЕННЯ ВУГЛЕВОДІВ У ХАРЧОВИХ КОМПОЗИЦІЯХ

Анотація

Subject. Using the example of confirming the chemical identity and determining the content of carrageenan in pork by various chemical and physicochemical methods, a comparative analysis of the ways of determining carbohydrates in food compositions was conducted. The problem of identifying and quantifying carbohydrates that are used to improve the consistency of products or can be introduced for the purpose of its falsification was considered. Purpose. An analytical comparison of possible methods for determining carbohydrates in food compositions was carried out and the most promising approaches for their qualitative and quantitative identification were selected. Methods. The gravimetric method, the Kjeldahl method, spectrophotometry, infrared spectroscopy and liquid chromatography were used for the research. Standard samples of carrageenan were studied; their hydrolysis and identification of decomposition products were carried out. Extracts were obtained from pork meat samples, from which fat and proteins were sequentially removed with subsequent analysis of residual components. To establish the conversion factor between the content of galactose and carrageenan, a spectrophotometric approach was used. Results. The identity of the IR spectra of the studied carrageenan samples was established and their characteristic structural features were confirmed. It was shown that liquid chromatography of hydrolyzed samples allows for reliable identification of carrageenan by the presence of galactose. In the extract obtained from pork, fat, proteins, amino acids and carbohydrates were separated, and the results of different methods were compared with each other. The presence of carbohydrates in an amount of about 1% was detected, which indicates a possible falsification of products with carrageenan. The most promising methods were determined to be IR spectroscopy and liquid chromatography, while the spectrophotometric method was recognized as not promising enough for the direct determination of carbohydrates in the studied samples. Scope of application of the results. The proposed approaches can be used to analyze food compositions to determine the content of carbohydrates, their identification, establish facts of falsification, and improve methods of quality control of food products.