Food adulteration poses a significant risk to food safety, especially in the case of milk and dairy products, which have garnered substantial attention from regulatory authorities. In this study, we developed a method for simultaneous detection of eight animal-derived components in milk and dairy products, employing multiplex PCR combined with gene membrane chip. These components encompass cow, yak, buffalo, goat, sheep, horse, donkey, and camel. Eight dairy-derived animal-specific probes, along with eukaryotic internal reference and plant-derived internal reference probes, were designed and immobilized on nylon membranes for hybridization with PCR products, enabling source identification. Utilizing reverse dot blot hybridization, the gene membrane chip facilitates the determination of eight dairy-derived components and the presence of plant-derived components. The method demonstrated an absolute sensitivity of 0.01 ng in the multiplex PCR and membrane chip hybridization system, with a detection limit of 0.1%, meeting market supervision requirements. Upon analysis of 75 commercially available dairy products, a mislabeling rate of 29.33% was revealed. Comparative analysis with conventional PCR and real-time quantitative PCR demonstrated the method's high specificity, good repeatability, and significantly improved detection throughput, thereby enhancing the screening efficiency for adulterants in dairy products and the targeted detection capability.
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