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The German National Reference Centre for Authentic Food (NRZ-Authent) and the competent German food control authorities of the federal states cooperated within the framework of the 10th joint Europol INTERPOL operation OPSON (OPSON X) in the detection of adulterated meat products. A total of 63 meat product samples were collected and analysed by the authorities using standard analytical procedures and subjected to a recently published 16S rDNA metabarcoding analysis. The sequence reads were analysed using 3 bioinformatics data processing strategies. The study aimed to gain additional data on the test samples regarding the authenticity of the declared species and to validate the 16S rDNA metabarcoding method with representative samples. The method was tested not only on 63 test samples, but also on 5 commercial samples from 2 interlaboratory comparison studies and 9 mock mixtures in parallel. The 16S rDNA metabarcoding method was able to detect species that were not target species of the used standard analytical methods, but failed, as shown previously, to detect fallow deer. Otherwise, the qualitative results of the 16S rDNA metabarcoding method were very similar to those of the methods currently in use by the German food control laboratories. Thus, the method has great potential to be used as a screening method for the authentication of mammal and poultry species in meat products.

In Germany, genetically modified organisms (GMO) analysis of food samples collected within the official food control is performed by the laboratories of the Federal States. The present report shows GMO analysis results from food samples of the years 2017 to 2021, including contaminations by unauthorized GMO, as well as genetically modified (GM) plant events authorized in the European Union. In addition to previous publications, evaluation of the aggregated food samples analysed for GMO components is shown. During this timeframe, 1077 (7.1%) out of 15,145 samples contained genetic modification. In 43 samples, DNA sequences of unauthorized GM plants were found. Additionally, for food derived from soybean, evaluations according to different product categories and the agronomic production (conventional and organic farming) are shown. Whereas in products from organic farming and in conventional soybeans labelled “without genetic engineering” GM soybeans were detected in 6.1% and 8.9%, of all tested samples, respectively, nearly 30% of all conventional soy samples yielded positive results below 0.1%. However, only in 0.7% of the overall analysed 5424 soybean samples GMO percentages of more than 0.1% were obtained. Generally, authorized GM plants were only found at low contamination levels. The labelling threshold of 0.9% for GM ingredients was exceeded only in 0.2% (maize) and 0.1% (soybean) samples, respectively. For monitoring purposes and risk evaluation, the data collection shall be continued.

German and imported honeys from non-European countries were analysed for the presence of veterinary drugs and of Paenibacillus larvaespores that might pose a potential threat transmitting AFB into local beehives. The coherence of application levels of antibiotics and the incidence of P. larvaespores were investigated. P. larvaestrains from imported honeys and strains isolated from local beehives were characterized by genetically subtyping to investigate a potential correlation of AFB-positive honeys and AFB cases in Hamburg. Whereas almost 50 % of the investigated non-EU honey samples contained at least 1 antibiotic residue, we detected antibiotic residues in only one out of 30 German honeys. As occurring antibiotic residues do not correlate with the presence of AFB spores the use of antibiotics in honey production remains obscure. We showed that the majority of AFB-positive samples from Hamburg and surrounding areas did not derive from imported AFB-positive honeys as the prevalent genotype in Hamburg is clearly distinct.

The inter-laboratory (=ring-trial) validation of 4 food allergen quantification methods using real-time PCR is described. Three single real-time PCR methods for the specific detection and quantification of sesame, almond and Brazil nut were used. Additionally, a multiplex real-time PCR method combining the detection of sesame, almond, Brazil nut and lupine was tested in parallel. Matrix based calibrants (rice cookies) spiked (=incurred) with defined amounts of sesame, almond, lupine and Brazil nut were applied for quantitative evaluation. Cookies based upon wheat and rice flour as well as sauce hollandaise powder each incurred with these allergenic ingredients in the range of 10–123 milligram per kilogram were used as ring-trial samples. The lowest spike level of 10 mg/kg could reproducibly be detected by 6 of 7 PCR systems. In quantitative evaluation of the results, reproducibility standard deviations of approximately 50 % and below were obtained. In addition, the effect of the food matrix on allergen quantification was examined. The range of “recoveries” over all matrices and methods was from 43 to 109 %.