Calvo Jorge H, Rodellar Clementina, Zaragoza Pilar, Osta Rosario
Laboratorio de Genética Bioquímica, Facultad de Veterinaria, C/Miguel Servet 177, 50013 Zaragoza, Spain.
J Agric Food Chem. 2002 Sep 11;50(19):5262-4. doi: 10.1021/jf020051a.
This research developed and evaluated a PCR procedure to detect beef in heated and unheated meat, sausages, and canned food, using a specific and sensitive method. To confirm the effectiveness and specificity of this fragment, we tested 45 cattle blood DNA samples (from different breeds) and obtained positive results. With 125 samples tested from other species, the specific beef amplification was not detected. Feed components intended for cattle nutrition were also checked, and bovine-derived material was detected. Using this method we can detect the degree of contamination up to 0.01% raw beef in pork. In the same way, 1% beef was detected in cooked meat mixtures and bovine-derived material in concentrate mixtures. Beef has been identified in both heated and unheated meat products, sausages, canned food, and hamburgers. In conclusion, specific PCR amplification of a repetitive DNA element seems to be a powerful technique for the identification of beef in processed and unprocessed food, because of its simplicity, specificity and sensitivity. Furthermore, feed components intended for cattle nutrition can be checked. The procedure is also much cheaper than other methods based on RFLPs-PCR, immunodiffusion, and other techniques that need expensive equipment.
本研究开发并评估了一种聚合酶链式反应（PCR）程序，该程序采用一种特异且灵敏的方法来检测加热和未加热的肉类、香肠及罐头食品中的牛肉成分。为证实该片段的有效性和特异性，我们检测了45份不同品种牛的血液DNA样本，均得到阳性结果。对125份其他物种的样本进行检测时，未检测到特异性的牛肉扩增。我们还检查了用于牛营养的饲料成分，检测到了牛源性物质。使用该方法，我们能够检测出猪肉中低至0.01%的生牛肉污染程度。同样地，在熟肉混合物中检测到了1%的牛肉，在浓缩混合物中检测到了牛源性物质。在加热和未加热的肉制品、香肠、罐头食品及汉堡中均鉴定出了牛肉成分。总之，由于其简单性、特异性和灵敏性，对重复DNA元件进行特异性PCR扩增似乎是一种用于鉴定加工和未加工食品中牛肉成分的有力技术。此外，还可检查用于牛营养的饲料成分。该程序也比基于限制性片段长度多态性-聚合酶链式反应（RFLPs-PCR）、免疫扩散及其他需要昂贵设备的技术的其他方法便宜得多。
