Detection of cows' milk in goats' cheeses inferred from mitochondrial DNA polymorphism

A new polymerase chain reaction (PCR)-based method was developed to detect cows' milk in oat cheese. This method is based on mitochondrial DNA (mtDNA) control region sequence variations. DNA extractions from 150 mg, of cheese were carried out using a spin column-based method. Subsequent PCR amplific ations of DNA were performed with cow specific primers, demonstrating the a bility to detect cows' milk in a variety of cheeses. This simple approach p rovides high quality DNA. and is shown to be very sensitive. with a detecti on limit of less than 0.1% of cows' milk. Analysis of an agarose gel digita l image allows a rough estimation of the percentage of cows' milk used in a dulteration.