European Food Research and Technology

, Volume 245, Issue 1, pp 151–157 | Cite as

Digital duplex versus real-time PCR for the determination of meat proportions from sausages containing pork and beef

  • René Köppel
  • Arthika Ganeshan
  • Franziska van Velsen
  • Stefan Weber
  • Jürg Schmid
  • Christoph Graf
  • Rupert Hochegger
Original Paper


According to Swiss law, sausages claiming to be made of veal have to contain at least 50% veal. To control the meat proportion of such products, control laboratories use real-time PCR. The measurement uncertainty of this method is at 30%. As a consequence, only extreme fraud can be reliably detected. To analyse sausages for their beef content with lower measurement uncertainty, a duplex droplet digital PCR was developed. Interlaboratory conversion factors were determined to enable weight-to-weight determination using values gained by real-time PCR and droplet digital PCR. Precision and accuracy were investigated examining reference sausages and sausages from the market. Comparing with real-time PCR, results from digital PCR showed a superior interlaboratory measurement uncertainty of 10% and will enable food control laboratories to determine also minor fraud.


Duplex droplet digital PCR Beef Pork Conversion factor Quantification 



We thank the cantonal laboratory of Zürich, the Official Food Control Authority of the Canton St.Gallen, Cantonal Office of Consumer Protection Bern, Switzerland and AGES CC Biochemie Vienna, Austria, for providing sample material and 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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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • René Köppel
    • 1
  • Arthika Ganeshan
    • 1
  • Franziska van Velsen
    • 1
  • Stefan Weber
    • 2
  • Jürg Schmid
    • 2
  • Christoph Graf
    • 3
  • Rupert Hochegger
    • 4
  1. 1.Official Food Control Authority of the Canton ZürichZurichSwitzerland
  2. 2.Official Food Control Authority of the Canton St. Gallen,St. GallenSwitzerland
  3. 3.Official Food Control Authority of the Canton BernBernSwitzerland
  4. 4.AGES CC Biochemie ViennaViennaAustria

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