Cow's milk allergens: Screening gene markers for the detection of milk ingredients in complex meat products

Cow's milk proteins are food allergens present in uncounted foodstuffs. By exploiting and comparing different regions of bovine genome, this work intended to develop a real-time PCR method to detect/quantify traces of milk in complex foods. Two mitochondrial (cytb and 12S rRNA) and two nuclear (beta-lactoglobulin and beta-casein) genes showed the most promising results by qualitative PCR. However, real-time PCR assays targeting nuclear genes revealed cross-reactivity with some meat species, while the 12S rRNA assay was the most specific (only minor reactivity with two species above 36 cycles of amplification), providing a linear dynamic range of 10-0.05% of cow's milk protein concentrate (MPC) in raw meat and cooked ham, with acceptable performance parameters. The results highlight the potentiality of the assay for the development of a novel method to quantify milk ingredients in meat products.