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DNA-analysis: enhancing the control of food authenticity through emerging technologies

corresponding

WERNER NADER1*, TORSTEN BRENDEL2, RAINER SCHUBBERT2

*Corresponding author

1. Eurofins Global Control GmbH, Grossmoorbogen 25, 21079 Hamburg, Germany

2. Eurofins Medigenomix GmbH, Anzinger Str. 7a, 85560 Ebersberg, Germany

Abstract

DNA-analysis is one of the tools used for verifying the safety and authenticity of food. This is demonstrated with two examples – DNA-fragment length analysis to detect pine nuts causing taste disturbances and microsatellite or STR (short tandem repeat) analysis to check Basmati rice authenticity. Pine nuts from Pinus armandii caused dysgeusia (taste distortion) among consumers and triggered 39 biotoxin notifications in the EU Rapid Alert System for Food and Feed. Two analytical methods – DNA-fragment length analysis and chemical fingerprinting – were developed to detect Pinus armandii nuts and notifications have decreased rapidly after the implementation of routine controls. Microsatellite analysis became the standard method for authenticity testing in the Code of Practice for Basmati rice, defined by the retailers, traders and rice millers in the United Kingdom. As a consequence the quality of Basmati rice improved measurably. In this article the development of these DNA based methods and the impact on food safety and authenticity are described. Further potential applications of these technologies are discussed.


INTRODUCTION

The quality, safety and authenticity of food are of principle interest for society and strictly regulated by legislation. The basic food law of the European Union, Regulation (EC) No 178/2002, focuses in article 8 on the protection of the ability of consumers to make informed choices in relation to the foods they consume. Fraudulent or deceptive practices, including the adulteration of food, and any other practices which may mislead the consumer should be prevented. A major tool for controlling authenticity is traceability, which is primarily based on documentation. However, documents can be falsified.
Information about the origin of a food product is often encrypted in its chemical composition. Rapid developments in science and technology during the last decades allow analysis and interpretation of these codes. An example of such a code is the stable isotope composition of a food product, which provides indications on the geographical origin, agricultural practice and adulterations, e.g. with artificial flavours (1).
A similar powerful technology utilises the genetic code encrypted in the DNA. With the discovery of the pol ...