可可粉中常见谷物成分的PCR检测技术研究

实验利用PCR方法检测可能掺入可可粉中的谷物成分。通过比较6种可可粉DNA的提取方法,建立了一种可靠、快速的方法,提出的DNA能够用于后续PCR反应。同时设计并验证了谷物通用引物的特异性和通用性,包括水稻、小麦、玉米、高粱米、荞麦、燕麦等常见谷物可通过1次PCR扩增筛选出来。模拟可可粉样品中谷物成分检出限达到0.1%。使用该方法检测了市场上购买的14个样品,均未检出常见谷物成分。为可可粉中可能添加的外源性物种检测提供了快速有效检测的方法和思路。

Detections of cereals in cocoa powder by PCR method

A PCR assay was established to detect cereals in cocoa powder.Six DNA extraction methods of cocoa powder were compared,and one rapid and efficient method which can produce enough qualified DNA for further PCR was established.In the mean time,a cereal common primer was designed,and its specificity and universality were tested.Common cereals,including rice,wheat,maize,sorghum,buckwheat and oat,can be detected through one PCR circle.The detection limit was 0.1% in simulated cocoa powder samples.No cereals were found in 14 sampled bought from the market.This method can produce fast and efficient method and direction for detection of extraneous materials in cocoa powder.