March 28, 2013
Novel DNA Test Detects Food Ingredients
redOrbit Staff & Wire Reports - Your Universe Online
European researchers have adapted the latest techniques of DNA sequencing to create a novel screening procedure that accurately determines the amount of animal, plant and microbial substances in foods.
In pilot studies, the new method was able to successfully detect the presence of a 1 percent content of horsemeat in products, and was able to determine the actual amount with a high degree of precision.
The researchers from Mainz University even found slight traces of the DNA of added mustard, lupin and soy in a test sausage prepared for calibration purposes, something that could also be of interest in allergy testing of foods.
"The innovative aspect in comparison with conventional DNA detection methods such as polymerase chain reaction, or PCR for short, is that by means of bioinformatic analysis of all biological DNA data available worldwide we can identify the presence of material from species that we would not otherwise expect. And, using a simple digital method of counting short snippets of DNA, we will also probably be able to determine the relative incidence of individual species-related material more precisely than was previously the case," said molecular geneticist Professor Dr. Thomas Hankeln, who developed the method in collaboration with bioinformaticist Professor Bertil Schmidt, Ph.D. and colleagues at the German and Swiss food control authorities.
Because of its potential, the method — dubbed 'All-Food-Seq' — has already attracted the attention of food inspection experts.
"This method is very interesting in connection with efforts to promote the molecular traceability of food," said Hermann Broll of the German Federal Institute for Risk Assessment in Berlin and Dr. RenÃ© KÃ¶ppel of the Zurich Cantonal Laboratory in Switzerland.
The new DNA test will be validated in comparison with conventional detection techniques in the near future, the researchers said.