Qualitative and quantitative identification of adulteration of milk powder using DNA extracted with a novel method

The extraction of high-quality DNA from processed dairy products is often the crucial step in an authentication process by PCR-based methods. In this study, we optimized a novel DNA extraction method for milk powder and used the extracted DNA for identification of milk powder based on PCR analysis. The DNA quality was assessed by amplifying target sequences from mitochondrial genes, as well as by monitoring the yield, purity, and integrity of the extracted DNA. In addition, a laboratory adulteration model of milk powder was detected by PCR-based methods (PCR and real-time PCR) using primers targeting the mitochondrial 12S rRNA gene. Results showed that a sufficient amount and quality of DNA could be isolated from milk powder with this method. Both PCR and real-time PCR detection of cow milk compositions in goat milk powder further confirmed the DNA extracted with this extraction method could be widely used in addressing milk powder adulterant by a PCR-based method.