Colloidal Gold Immunochromatography and ELISA Traceability of Tetracycline Residues from Raw Milk to its Dairy Products

Background/Aim: The presence of tetracycline (TC) and its residues in raw milk and milk dairy products poses a threat to human health due to the induction of antibiotic resistance of bacteria that can be transmitted between animals, humans, and the environment. The aim of this study was to investigate the transfer of TC from raw milk to different dairy products: pasteurized milk, boiled milk, sour milk, skimmed milk, and cottage cheese. We analyzed samples of milk from different sources: household farmers, local farms, and milk factories. Materials and Methods: The analyses of TC in milk and dairy products were performed using colloidal gold immunochromatography assay (GICA) and enzymelinked immunosorbent assay (ELISA). Results: The highest content of TC was found in the milk purchased from local household farmers; therefore, these samples were chosen for the study of TC transfer to dairy products. TC was also found in sour milk at levels comparable with those obtained in raw milk. The average TC content decreased following heat treatment of the milk, as follows: for pasteurized milk 22.07%

Automated summary

The study investigated the transfer of tetracycline (TC) from raw milk to different dairy products. The highest TC content was found in milk from household farmers, while sour milk had TC levels comparable to raw milk. Heat treatment of the milk resulted in a decrease in TC content.