Abstract: In order to accurately quantify the proportion of mutton-derived ingredients in meat products, the single-copy gene of mutton for quantitatively detection of mutton ingredients by the droplet digital polymerase chain reaction (ddPCR) was established in meat products. The result showed that an internal standard for quantitative analysis of the proportion of mutton-derived ingredients with ddPCR was established based on the linear relationship between DNA copy number and sample quality by adding beef as internal standard. The method developed here realized one-step transformation from target gene copy number to sample quality. The detection limit reached 0.01% of sheep-source ingredients which equaled to 0.12 copies/μL. In reality, it could accurately quantify the mutton-derived ingredients which was more than 5% of mutton in meat products. The quantitative analysis of commercial samples showed that ddPCR could accurately determine the proportion of mutton-derived ingredients in meat samples. So ddPCR had great potential in the detection and adulteration identification of mutton-derived ingredients in meat and meat products.
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