Species – specific PCR test for the quick recognition of equine tissue in raw and processed beef meat mixtures

Abstract PCR was applied for the discovery of adulteration of crude and processed beef meat with horse and donkey tissue. This was performed by blending (w/w) horse or donkey meat to beef meat in an extent up to 1:10000 (0.01%). The sensitivity was resolved as high as 0.01%. All used primers showed specificity in the PCR reactions utilizing layout DNAs from three animal species. PCR application on 96 beef meat and meat product samples gathered randomly from street vendors and prominent retail markets (24 of burger, 16 of minced meat, 24 of kofta, 16 of sausage, 7 of raw meat and 9 of launcheon) uncovered 6 positive for donkey tissue (3 from sausage, 2 from minced meat and 1 from kofta) and 2 positive for horse tissue (from sausage). This basic PCR strategy effectively distinguished adulteration of raw and processed beef meat samples with horse and donkey tissue. This work also highlights on the severity of the meat adulteration problem in Egypt.

摘要：本研究采用聚合酶链式反应（Polymerase Chain Reaction, PCR）技术，用于检测生牛肉及加工牛肉制品中掺杂马、驴源组织的掺假行为。实验通过将马肉或驴肉以1:10000（即0.01%）的质量比（w/w）混入牛肉中开展验证，结果显示该方法的检测灵敏度可达0.01%。所有使用的引物在以三种动物的基因组DNA为模板的PCR反应中均具备特异性。研究人员从街头摊贩及知名零售市场随机采集96份牛肉及肉制品样本，具体包括24份汉堡制品、16份肉馅、24份库夫塔（Kofta）肉丸、16份香肠、7份生鲜牛肉及9份午餐肉（原文本拼写为launcheon，应为luncheon meat）。经检测，其中6份样本呈驴源组织阳性（3份来自香肠、2份来自肉馅、1份来自库夫塔肉丸），2份样本呈马源组织阳性（均来自香肠）。该简易PCR策略可有效鉴别生牛肉及加工牛肉制品中掺杂马、驴源组织的掺假情况。本研究同时凸显了埃及肉类掺假问题的严峻性。