THE USE OF MODEL SAMPLES TO ESTIMATE THE LEVEL OF FRAUDULENT ADDITION OF PORK MEAT IN POULTRY MEAT BY REAL-TIME PCR

摘要

The undeclared presence of meat species in grounded and comminuted meat products is a concern because it represents an economic fraud, but also for public health, ethical and religious reasons. Meat species identification allows detecting adulterations such as the fraudulent substitution of cheaper meats for more expensive ones. In this work, model samples were prepared at the laboratory containing poultry meat added with known amounts of pork meat. DNA was extracted from the model samples and a real-time polymerase chain reaction (PCR) technique using the SYBR Green Ⅰ fluorescent dye coupled to melting curve analysis was proposed to obtain a predicting model to estimate the level of possible fraudulent addition of pork meat. The addition of pork meat was detected in the range of 0.1% to 25%, with a high correlation coefficient and PCR efficiency. Calibration curves were obtained with the cycle threshold (Ct) values by using the ΔΔCt method. The application of the approach to blind samples demonstrated the suitability of the proposed methodology for estimating the level of porcine DNA in meat mixtures.