Jonker K M, Tilburg J J H C, Hagele G H, de Boer E
Food and Consumer Product Safety Authority, Zutphen, The Netherlands.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2008 May;25(5):527-33. doi: 10.1080/02652030701584041.
One of the most convenient methods for the identification of animal species in processed meat products is the examination of DNA sequences. Real-time polymerase chain reaction (qPCR) techniques are particularly suitable because even small fragments of DNA formed during heat processing of the meat can be amplified and identified. A real-time PCR method has been developed and evaluated for the identification of processed meat products. In test mixtures containing beef, pork, horse, mutton, chicken and turkey, it was possible to identify these species down to a level of 0.05%. By adjusting the number of cycles, it was possible to detect levels as low as 0.01% of these species. Cross-reactivity between these species was not found, except for pure horsemeat (250 ng DNA) in the assay for turkey meat. Cross-reactivity of deer, roe, ostrich, kangaroo, goat, domestic duck, mallard, goose, pigeon, guinea fowl, quail and pheasant was also investigated and it was found that amounts as high as 250 ng DNA of these species in the reaction vial did not result in (false) positive signals except for amounts higher than 125 ng deer DNA and higher than 50 ng pigeon DNA in the determination of chicken and beef, respectively. More than 150 meat samples were examined using DNA hybridization and real-time PCR. A comparison of the results showed a better performance of the real-time procedure compared to DNA hybridization.
鉴定加工肉制品中动物物种最便捷的方法之一是检测DNA序列。实时聚合酶链反应（qPCR）技术尤为适用，因为即使在肉类热处理过程中形成的小片段DNA也能被扩增和鉴定。一种用于鉴定加工肉制品的实时PCR方法已被开发并评估。在含有牛肉、猪肉、马肉、羊肉、鸡肉和火鸡肉的测试混合物中，能够鉴定出低至0.05%含量水平的这些物种。通过调整循环次数，能够检测到低至0.01%含量水平的这些物种。除了在火鸡肉检测试验中纯马肉（250 ng DNA）出现交叉反应外，未发现这些物种之间存在交叉反应。还对鹿肉、狍肉、鸵鸟肉、袋鼠肉、羊肉、家鸭肉、野鸭、鹅肉、鸽肉、珍珠鸡肉、鹌鹑肉和雉鸡肉的交叉反应进行了研究，结果发现，反应管中这些物种高达250 ng DNA的量不会产生（假）阳性信号，但在鸡肉和牛肉检测中，分别有高于125 ng的鹿肉DNA和高于50 ng的鸽肉DNA时除外。使用DNA杂交和实时PCR对150多个肉类样本进行了检测。结果比较表明，与DNA杂交相比，实时检测程序表现更佳。
