Food ecology: antioxidant activity and free amino acids in milk under cadmium contamination
Authors:
Roman O. Budkevich, Nikita M. Fedortsov, Elena V. Budkevich, Ivan A. Evdokimov
Abstract:
The authors studied cadmium levels in milk from 2014 to 2022 in an ecologically unfavorable region (Nevinnomyssk and Kochubeevsky District, Stavropol Krai) and assessed the total antioxidant activity (TAA) and free amino acids in milk compared to a relatively clean region (Stavropol and Shpakovsky District). The authors used the FRAP method, the amperometric method, and the assessment of antioxidant activity in a model system with yolk lipoproteins to evaluate the TAA. Free amino acids were analyzed using a post-column ninhydrin reaction on an ARACUS amino acid analyzer (Abacus, Germany). Data were evaluated using the Shapiro–Wilk and Levene tests and compared using the Mann–Whitney test using Statistica 10.0 software. In the region with an environmentally unfavorable situation, the maximum cadmium level was detected in 2019 – 0.025 mg/kg, with no exceedance of the standard in milk for the period 2014–2022. Elevated cadmium levels in raw milk reduce its TAA, assessed using various methods. Concentrations of certain free amino acids (L-tyrosine, L-isoleucine, L-cystine, L-methionine, and cystathionine) increase. An increase in S-containing amino acids indicates increased activity of the protein antioxidant system of cows in an ecologically unfavorable region. Keeping cows in polluted areas affects cadmium levels in milk, activates the animals' antioxidant system, and alters the regulation of free amino acid metabolism. Biochemical changes in milk can affect the technological properties and nutritional value of milk. Additional research is needed to reduce the impact of cadmium on animal health and physiological functions.
Keywords:
milk; cadmium; antioxidants; amino acids; food ecology
For citation:
Budkevich R.O., Fedortsov N.M., Budkevich E.V., Evdokimov I.A. Food ecology: antioxidant activity and free amino acids in milk under cadmium contamination. Индустрия питания|Food Industry. 2026. Vol. 11, No. 2. Pp. 55–65. DOI: 10.29141/2500-1922-2026-11- 2-6. EDN: RPJBJU.
