Duplex digital PCR for the determination of meat proportions of sausages containing meat from chicken, turkey, horse, cow, pig and sheep
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The probability of accidental or intentional addition of another species of meat in meat products is high. Meat is expensive and in the context of food waste, it is reasonable to reduce loss of this precious material during the production. However, the line between fraud and waste reduction is thin. Minor variations, e.g., up to 1% of unexpected meat content, may be tolerated. But to distinguish between minor variations and severe deviations to the list of ingredients, analytical methods with a low measurement uncertainty are required. The recent introduction of digital PCR indicated that this new method may lead to a reduction of the measurement uncertainty. We present the measurement of proportions of beef, pork, chicken, turkey, sheep and horse meat in a cooked sausage matrix and a procedure to calculate the proportions (w/w) based on target DNA concentrations measured using droplet digital PCR. Six laboratories applied these methods and determined the w/w proportions of 20 sausage samples. It was shown that these methods in conjunction with conversion factors can be used to estimate meat proportions in mixed meat products with superior accuracy and precision compared to results generated by real-time PCR.
KeywordsDroplet digital PCR Chicken Turkey Beef Pork Horse Sheep Conversion factor
We thank the cantonal laboratory of Zürich, the Official Food Control Authority of the Canton St. Gallen, Cantonal Office of Consumer Protection Bern. Austrian Agency for Health and Food Safety, Vienna, Austria, Chemisches und Veterinäruntersuchungsamt Freiburg, Germany and National Measurement Institute, Sindey, Australia and Berlin-Brandenburg State Laboratory (LLBB), Germany, for providing the resources for this work.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
Compliance with ethics requirements
This article does not contain any studies with human or living animal subjects.
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