Identification of potential markers for detecting milk adulteration in two donkey breeds with cow milk using a proteomics approach

This is the authors' abstract. We don't add key points for this paper.

Donkey milk (DM) is nutritious and hypoallergenic but expensive, making it prone to adulteration with cow milk (CM). This study applied label-free proteomics to detect CM adulteration in Dezhou and Xinjiang DM, and key markers were validated using capillary electrophoresis. Cow-derived proteins such as κ-casein, α s1 -casein, β-casein, α-lactalbumin, β-lactoglobulin, milk fat globule-EGF factor 8 (MFGE8) protein, and glycosylation-dependent cell adhesion molecule 1 (GlyCAM1) were detectable at the lowest tested adulteration level of 2%, whereas xanthine dehydrogenase and lipoprotein lipase were detectable at 5% adulteration. Most cow-specific proteins showed consistent detection thresholds across both DM sources, whereas β-2-microglobulin, immunoglobulin light chain, and lactoferrin exhibited breed-dependent variability. Capillary electrophoresis validated the proteomic markers αS1-casein and β-lactoglobulin. These results support the potential utility of cow-specific protein markers for detecting donkey milk adulteration and provide a basis for the future development of rapid authentication methods.