Volume: 3, 2024
3rd International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland:
ENVIRONMENT – PLANT – ANIMAL – PRODUCT
Abstract number: H009
DOI: https://doi.org/10.24326/ICDSUPL3.H009
Published online: 24 April 2024
ICDSUPL, 3, H009 (2024)
Optimization of procedures for preparing milk samples and whey protein powders for vitamin determination using the ELISA method
Anna Lipian-Głos1*, Anna Stępniowska1, Paulina Osowska1, Jagoda Szafrańska2, Magdalena Krauze1, Bartosz Sołowiej2, Katarzyna Ognik1
1 Department Biochemistry and Toxicology, Faculty of Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland
2 Department of Dairy Technology and Functional Foods, Faculty of Food Sciences and Biotechnology, University of Life Sciences in Lublin, Skromna 8, 20-704 Lublin, Poland
* Corresponding author: anna.lipian@up.lublin.pl
Abstract
Milk and its products are an important source of vitamins, primarily B vitamins, which, in addition to fat-soluble vitamins, have a very significant impact on metabolism, homeostasis and proper human nutrition. Due to the complex matrix, milk samples must be properly prepared. Therefore, the aim of the work was to optimize the procedure for preparing milk samples and whey protein powders (WPC) for the determination of selected B vitamins (B2, B6, B12) and fat-soluble vitamins (A, D, E). Milk samples in the amount of 3 mL were homogenized with 3 mL of buffered saline with pH = 7.4 (PBS) by placing them in an ultrasonic bath for 5 min. Additionally, it was tested whether the use of liquid-liquid extraction would reduce interference. For this purpose, 1.5 or 3 mL of chloroform was added to milk samples (3 mL), the samples were homogenized and centrifuged at 4500 g for 5 min. After centrifugation, two phases were obtained: water and chloroform. A chloroform layer was taken for the determination of fat-soluble vitamins, and an aqueous layer was taken for the determination of water-soluble vitamins. The samples prepared in this way were dosed onto an ELISA plate to determine individual vitamins. Due to the low fat content in milk, liquid-liquid extraction using chloroform was not necessary. For vitamin determination using the ELISA method, milk samples were prepared by homogenizing the product with PBS. WPC powder samples were prepared by weighing approximately 1 g of powder, adding 10 mL of PBS and placing the samples in ultrasound for 5 min. The samples prepared in this way were dosed onto an ELISA plate for determining the tested parameters. The obtained results allow us to conclude that by appropriately preparing dairy samples, vitamins can be determined using ELISA kits.
Task titled: “Research network of natural science universities for the development of the Polish dairy sector – research project” is financed under a special-purpose subsidy from the Minister of Education and Science (MEiN/2023/DPI/2862).
Keywords: cow milk, whey protein powder, B vitamins, vitamin A, vitamin D
How to cite
A. Lipian-Głos, A. Stępniowska, P. Osowska, J. Szafrańska, M. Krauze, B. Sołowiej, K. Ognik, 2024. Optimization of procedures for preparing milk samples and whey protein powders for vitamin determination using the ELISA method. In: 3rd International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL3.H009