Uric acid as a marker of milk microbiological spoilage

Abstract

Uric acid is an important component of milk, which has antioxidant properties and protects it from rapid microbiological spoilage. The article studies the change in uric acid content during unwanted spoilage of pasteurized and unpasteurized milk using a developed voltammetric sensor based on a carbon veil. The sensor allows to estimate the content of uric acid in a wide range of concentrations without the influence of the complex matrix of the test sample on the determination result. It has been established that the uric acid content in pasteurized milk is several times less than in unpasteurized milk. With microbiological spoilage of milk, the uric acid content decreases by 40–100 %, which makes it possible to use this biologically active compound as a marker of milk spoilage. The developed sensor provides high reproducibility (Sr≤4.6 %) and accuracy of results, as evidenced by the recovery close to 100 %. The sensor can be used to control the quality and safety of milk used in technological processes for the production of dairy products.