Official Food Control Laboratories Research Articles

Gelatin medium for preserving of Trichinella spp. for quality control in laboratories - estimation of larvae viability.

Official food control laboratories ensure food safety using reliable, validated methods. Council Regulations (EC) No. 853/2004, 854/2004 and 882/2004 of the European Parliament established hygiene rules the production of food of animal origin, together with requirements for official controls. This leads to detailed requirements for Trichinella control set out in Commission Implementing Regulation (EU) 2015/1375 of 10 August 2015. These regulations require the laboratory to participate in proficiency testing (PT) to confirm their competence and improve the quality of testing, and require the PT Organizer to use methods for the preparation and preservation of parasite larvae in order to evaluate and improve detection. Traditional methods of preparing such larvae expose them to rapid degradation, making it necessary to simultaneously isolate the larvae and place them in meatballs to ensure quality. We developed a technique for preserving of Trichinella spp. for quality control such as PT sample preparation. The procedure protects larvae against toxic oxygen activity and bacterial destruction via a gelatin barrier. To estimate the viability of larvae preserved by this method, gelatin capsules with 10 larvae of T. spiralis in each were stored (4-8 °C) during 45 days of an experiment. Samples were tested at 2 day intervals (3 samples each day of testing). In total, 75 samples were tested. Larvae remained alive up to 3 weeks. The number of living larvae diminished after 27 days through day 43, after which no living larvae were observed. The gelatin medium procedure facilitated easy, high-throughput sample preparation and supported 100% recovery for 3 weeks. The method allows fast, efficient and accurate PT sample preparation.

GMO analysis results from official food control laboratories in Germany from 2017 to 2021

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.

Analytical Approaches in Official Food Safety Control: An LC-Orbitrap-HRMS Screening Method for the Multiresidue Determination of Antibiotics in Cow, Sheep, and Goat Milk.

The presence of unauthorized substances, such as residues of veterinary medicines or chemical contaminants, in food can represent a possible health concern. For this reason, a complete legislative framework has been established in the European Union (EU), which defines the maximum limits allowed in food and carries out surveillance programs to control the presence of these substances. Official food control laboratories, in order to ensure a high level of consumer protection, must respond to the challenge of improving and harmonizing the performance of the analytical methods used for the analysis of residues of authorized, unauthorized, or prohibited pharmacologically active substances. Laboratories must also consider the state of the art of the analytical methodologies and the performance requirements of current legislation. The aim of this work was to develop a multiresidue method for the determination of antibiotics in milk, compliant with the criteria and procedures established by Commission Implementing Regulation (EU) 2021/808. The method uses an LC-Orbitrap-HRMS for the determination of 57 molecules of antibiotic and active antibacterial substances belonging to different chemical classes (beta-lactams, tetracyclines, sulfonamides, quinolones, pleuromutilins, macrolides, and lincosamides) in bovine, ovine, and goat milk samples. It provides a simple and quick sample pretreatment and a subsequent identification phase of analytes, at concentrations equal to or lower than the maximum residual limit (MRL), in compliance with Commission Regulation (EU) 2010/37. The validation parameters: selectivity, stability, applicability, and detection capability (ccβ), are in agreement with the requirements of Commission Implementing Regulation (EU) 2021/808 and demonstrated the effectiveness of the method in detecting veterinary drug residues at the target screening concentration (at the MRL level or below), with a false positive rate of less than 5%. This method represents an effective solution for detecting antibiotics in milk, which can be successfully applied in routine analyses for official food control plans.

Interlaboratory Validation of a DNA Metabarcoding Assay for Mammalian and Poultry Species to Detect Food Adulteration.

Meat species authentication in food is most commonly based on the detection of genetic variations. Official food control laboratories frequently apply single and multiplex real-time polymerase chain reaction (PCR) assays and/or DNA arrays. However, in the near future, DNA metabarcoding, the generation of PCR products for DNA barcodes, followed by massively parallel sequencing by next generation sequencing (NGS) technologies, could be an attractive alternative. DNA metabarcoding is superior to well-established methodologies since it allows simultaneous identification of a wide variety of species not only in individual foodstuffs but even in complex mixtures. We have recently published a DNA metabarcoding assay for the identification and differentiation of 15 mammalian species and six poultry species. With the aim to harmonize analytical methods for food authentication across EU Member States, the DNA metabarcoding assay has been tested in an interlaboratory ring trial including 15 laboratories. Each laboratory analyzed 16 anonymously labelled samples (eight samples, two subsamples each), comprising six DNA extract mixtures, one DNA extract from a model sausage, and one DNA extract from maize (negative control). Evaluation of data on repeatability, reproducibility, robustness, and measurement uncertainty indicated that the DNA metabarcoding method is applicable for meat species authentication in routine analysis.

The Barcoding Table of Animal Species (BaTAnS): a new tool to select appropriate methods for animal species identification using DNA barcoding.

Food and feed products derived from animal materials have a long history of being adulterated. Methods for the identification of animal samples based on DNA barcoding are very potent tools to reveal species substitution. Since numerous DNA barcoding methods are available for different taxa, it is challenging to choose an appropriate and verified method for each sample in question. To overcome this obstacle the working group "Molecular biological methods for plant and animal species differentiation" developed the "Barcoding Table of Animal Species". This working group is established through the German food and feed law and is mandated to validate standard methods, especially for the official food and feed control laboratories in Germany. In this paper, a collection of currently available and verified DNA barcoding methods for the identification of animal species is presented as a Microsoft Excel® file-"The Barcoding Table of Animal Species (BaTAnS)". It consists of several components: The method collection, the results collection and a section for reporting new entries and problems. It is focusing on the validity and applicability of DNA barcoding methods to test food and feed products for correct species declaration. Each method is listed with its reference and is verified by at least two laboratories for their applicability. Since additional information will be available in future, this table will be updated regularly. The BaTAnS is an easy tool that helps to choose the right verified method to identify a certain specimen to taxon, genus or species level in food samples.

Importance of harmonised sample preparation for moisture and protein content determinations in official food control laboratories: A poultry meat case study

Commission Regulation (EC) 543/2008 limits moisture and protein contents in poultry meat. However, this regulation leaves room for interpretation regarding sample homogenisation, potentially affecting comparability of laboratory results. Therefore, a proficiency test and sample homogenisation study were organised amongst 19 European National Reference Laboratories (NRL). In the proficiency test, three different pre-homogenised chicken samples (fillets, drumsticks and carcasses) were analysed. Only one NRL produced unsatisfactory results. In the homogenisation study, NRLs were supplied with uniform fillet, drumstick and carcass materials. Homogenisation was performed according to the NRLs in-house methods. Five NRLs did not return satisfactory results. As these NRLs produced satisfactory results in the proficiency test, their increase in z-scores was related to their homogenisation practices. Overall, scattering of individual results was higher for drumsticks compared to fillets and carcasses. Homogenisation practices for poultry meat introduced significant differences in moisture and protein results and standardisation is therefore advisable.

Official food control laboratories in Germany: results of GMO analyses from 2012 to 2016

Official food control laboratories in Germany: results of GMO analyses from 2012 to 2016

Action Levels for Food Allergens: An Approach for Official Food Control in Germany.

Official food control laboratories in Germany have established internal action values for the assessment of analytical results of food allergens especially obtained from samples without declaration of the specified allergen. A pragmatic approach was chosen considering the current situation for European food information legislation. Accordingly, when a positive result is obtained for an unlabeled allergen, it is not necessarily an irregularity if it can be demonstrated that the result was caused by cross-contamination. Action values take into account current analytical experiences as well as published allergologic reference doses. They are considered as internal de minimis thresholds by food control authorities that are used to support laboratories in the decision-making process and when a written expert opinion is requested by an enforcement authority. If only minor traces are detected at concentrations below the action values, further investigation of the issue and inspections at the location of manufacture can be abandoned. The present report includes a collection of results from official food control laboratories in Germany that have been evaluated in line with the aforementioned system of action levels.

Food Adulteration in Switzerland: From 'Ravioli' over 'Springbok' to 'Disco Sushi'.

The driving force behind food adulteration is monetary profit and this has remained unchanged for at least the last hundred years. Food adulterations were and still are difficult to uncover because they occur mostly in an unpredictable and unexpected way. Very often food falsifiers take advantage of modern technology in such a way that food adulterations are difficult or sometimes even impossible to detect. Targets for food adulteration were and still are highly priced food items such as spirits, meat, seafood and olive oil. Although difficult to detect, food adulterations were in the past strong driving forces for the development of adequate detection methods in the official food control laboratories and for the enforcement of the food law. A very prominent example in this context is the 'Ravioli scandal' in Switzerland in the late 1970s which showed that cheap second-class meat could be processed into products without being discovered for long time. As a consequence the official food control laboratories in Switzerland were reinforced with more laboratory equipment and technical staff. With the introduction of new detection principles such as DNA-based analytical methods new kinds of food adulteration could and can be uncovered. Analytical methods have their limits and in some cases of food fraud there are no analytical means to detect them. In such cases the examination of trade by checking of accounts is the method of choice.

Meta-audit of laboratory ISO accreditation inspections: measuring the old emperor's clothes.

Accreditation to ISO/IEC 17025 is required for EC official food control and veterinary laboratories by Regulation (EC) No. 882/2004. Measurements in hospital laboratories and clinics are increasingly accredited to ISO/IEC 15189. Both of these management standards arose from command and control military standards for factory inspection during World War II. They rely on auditing of compliance and have not been validated internally as assessment bodies require of those they accredit. Neither have they been validated to criteria outside their own ideology such as the Cochrane principles of evidence-based medicine which might establish whether any benefit exceeds their cost. We undertook a retrospective meta-audit over 14 years of internal and external laboratory audits that checked compliance with ISO 17025 in a public health laboratory. Most noncompliances arose solely from clauses in the standard and would not affect users. No effect was likely from 91% of these. Fewer than 1% of noncompliances were likely to have consequences for the validity of results or quality of service. The ISO system of compliance auditing has the performance characteristics of a poor screening test. It adds substantially to costs and generates more noise (false positives) than informative signal. Ethical use of resources indicates that management standards should not be used unless proven to deliver the efficacy, effectiveness, and value required of modern healthcare interventions.

Can analytical chemists do molecular biology? A survey of the up-skilling of the UK official food control system in DNA food authenticity techniques

That food accurately matches its description or labelling (food authenticity) is increasingly important to consumers and the agrifood sector. Its converse – mislabelling or misdescription or food fraud (when carried out for financial gain), is detrimental to both. A range of activities is used by enforcement authorities to establish authenticity and detect fraud including sampling and analysis. The UK Government, in a 20 year programme, has developed many novel analytical authenticity approaches including high resolution NMR, carbon isotope ratio analysis and DNA techniques. The flexibility, relatively lower costs and probative value of DNA methods render them particularly effective. However their deployment in the forensic environment of UK Official Food Control Laboratories (OCLs), staffed mainly by analytical chemists, required knowledge transfer (KT) of molecular biology techniques. The KT was carried out by the Food Standards Agency's Food Authenticity Programme (now transferred to Defra), and we present here the results of an assessment of its effectiveness. The findings highlight that the KT was well planned and highly effective. Competence in molecular biology in OCLs rose from 22% prior to the KT, based on qualifications and experience, to 69% after the KT based on embedding a suite of DNA methods in 11 out of 16 eligible laboratories. The transfer of 5 DNA methods (fish species, meat and exotic meat species, bushmeat species, Basmati rice, and orange juice adulteration with mandarin juice) have given OCLs an increased range of effectiveness with fish species identification having been particularly successfully applied and resulting in successful prosecutions of fraudulent activity. Given the current financial constraints in UK OCLs, a beneficial outcome has been a strategic refocussing of effort boosting enthusiasm and excitement for food authenticity issues. A further outcome of the transfer and evidence of the uptake of DNA technology has been the adoption of Real Time Polymerase Chain Reaction techniques by a critical mass (31.3%) of OCLs, permitting their advanced application to problematic authenticity issues such as the detection of adulteration of durum wheat pasta with common wheat, detection of meat ingredients in vegetarian foods, and the quantitative determination of GMOs in single ingredient foods such as pasta, rice and soya. Other recommendations arising out of the study are to adapt, to a lab-on-a-chip platform, DNA methods for pig and cattle breed authentication including wild boar, and an improved Basmati rice authentication. Finally, sustainable deployment of DNA methods to address food authenticity and fraud hinges on regulatory salience of the need for it and this, along with future priorities, should be kept under regular review.

Preparation of Test Material and Evaluation of a Proficiency Test for Official Food Control Laboratories on the Determination of Polycyclic Aromatic Hydrocarbons in Baby Food

A proficiency test on the determination of polycyclic aromatic hydrocarbons (PAHs) was organized by the German National Reference Laboratory for PAH in 2010. The test samples were produced by spiking cereal-based instant baby food with PAHs at concentration levels between 0.6 and 3.8 μg/kg; homogeneity and stability of the test material were verified before sample dispatch. Twenty-one official laboratories from Germany and Austria participated in the test and the evaluation of the test was done by applying methods of robust statistics. The individual performance was assessed with the help of z-scores. As to the quantitative results, the dispersion of data for the most important group of benzo(a)pyrene (BaP), benz(a)anthracene (BaA), benzo(b)fluoranthene (BbF), and chrysene (CHR) appeared to be acceptable, with a relative robust standard deviation ranging from 13.2% for BbF to 26.7% for BaA. In total, the performance of one laboratory had to be rated as unsatisfactory because of a result for BaP outside the limits of tolerance. The methods applied in the test may be considered to be comparable, as no significant effects in the distribution of data could be attributed to certain analytical procedures.

Determination of 3‐MCPD esters in edible oil – methods of analysis and comparability of results

AbstractThe discovery of fatty acid esters of 3‐chloropropane‐1,2‐diol (3‐MCPD) in edible oil products initiated food monitoring campaigns in many EU Member States. As the determination of 3‐MCPD esters was new to most laboratories, questions on the reliability of the produced analysis data were raised. In response to this, the Institute for Reference Materials and Measurements (IRMM) of the European Commission's Joint Research Centre (JRC) organised a proficiency test on the determination of 3‐chloropropane‐1,2‐diol esters (3‐MCPD esters) in edible oils. The aim of this proficiency test was to scrutinise the capabilities of official food control laboratories, private food control laboratories as well as laboratories from food industry to determine the 3‐MCPD esters content of edible oils. The study was carried out in accordance with “The International Harmonised Protocol for the Proficiency Testing of Analytical Chemistry Laboratories” and ISO Guide 43. The test materials dispatched to the participants were: refined palm oil, extra virgin olive oil spiked with 3‐chloropropane‐1,2‐dioleate and 3‐MCPD standard solution in sodium chloride. Altogether 41 laboratories from 11 EU Member States, Switzerland and Macedonia subscribed for participation in the study. The analysis task was to determine the 3‐MCPD esters content as total 3‐MCPD content of the test samples. Participants were free to choose their analysis methods. In total, 34 laboratories reported results to the organisers of the study. The performance of laboratories in the determination of 3‐MCPD esters in edible oils was expressed by z‐scores. About 56% of the participants performed satisfactorily in the determination of 3‐MCPD esters in palm oil and 85% for the spiked extra virgin olive oil test sample. The study revealed that the direct transesterification of the sample without the prior removal of glycidol esters might lead to strong positive bias.

Multiplex real-time PCR for the detection and quantification of DNA from beef, pork, horse and sheep

Many meat products are composed of two or more meat species. To determine the proportion of these meat fractions, a quantitative multiplex PCR was developed for the quantification of beef, pork, chicken and turkey. This system proved its applicability, precision and accuracy in examining different meat products from the market. Thus it allows the efficient control of composed meat products in official food control and production control laboratories.

European Union database of acrylamide levels in food: Update and critical review of data collection

The European Commission's Directorate General Joint Research Centre has been collecting data produced by European Union Member States on the acrylamide content of food since 2003. More than 9000 individual data points have been received from official food control laboratories directly or via their Competent Authorities, and from the food industry. Before being entered into the database, the data were assessed for their reliability. This paper presents an update of the database as well as results of the evaluation of data for selected food commodities in order to establish a trend concerning the content of acrylamide in food. Experience gained with the data collection and data assessment are described and recommendations for future data collection initiatives given.

Qualitative and Quantitative Detection of Protein and Genetic Traits in Genetically Modified Food

Due to the market introduction of genetically modified organisms (GMOs) in crops, foods, and ingredients, legislation worldwide came face to face with the question of the use and labeling requirements on GMO crops and their derivatives. In this review, protein- and DNA-based methods, such as enzyme-linked immunosorbent assay, western blots, and qualitative and quantitative polymerase chain reaction PCR (Q-PCR) are reviewed. Qualitative detection methods for genetically modified (GM) sequences in foods have evolved rapidly during the past years. The sensitivity of these systems is extremely high, even for processed foodstuffs. However, the availability of quantitative detection methods for GMO analysis is an important prerequisite for the introduction of threshold limits for GMOs in food. The recently introduced labeling threshold for GMOs in food ingredients by the European Union has forced official food control laboratories to apply quantitative PCR methods. Taking the precision of quantitative PCR detection methods into account, suitable sample plans and sample sizes for GMO analysis are discussed. As quantitative GMO detection methods measure GMO contents of samples in relation to reference material, priority must be given to international agreements and standardization on certified reference materials. The rapidly increasing number of GM foods on the market demands the development of more advanced multidetection systems, such as microarray technology. Challenges and problems arising from the inability to detect GM foods for which the modified sequence is unknown, the lengthy standardization procedures, and the need to continuously update databases comprising commercially available GM foods and the respective detection strategies are also discussed.

Ochratoxin A (OTA) in Kaffee — Vergleichende Auswertung bundesweiter Daten der Jahre 1995–1999 und 2000–2002

Ochratoxin A concentrations from a total of 1223 samples from green, roasted and ground, decaffeinated and low acid and instant coffee analysed during 1995–1999 and 2000–2002 by German Official Food Control Laboratories were compared. Median concentrations, determined by statistical process analysis decreased within each group from the early group up to 2002. The rates of rejection were calculated on the basis of the recent data for green and roasted and ground coffee which may occur when particular maximum residue limits were set. Contamination rates from green coffee showed significant differences in their OTA concentrations depending on their geographical origin.

Validation of PCR Methods for Quantitation of Genetically Modified Plants in Food

For enforcement of the recently introduced labeling threshold for genetically modified organisms (GMOs) in food ingredients, quantitative detection methods such as quantitative competitive (QC-PCR) and real-time PCR are applied by official food control laboratories. The experiences of 3 European food control laboratories in validating such methods were compared to describe realistic performance characteristics of quantitative PCR detection methods. The limit of quantitation (LOQ) of GMO-specific, real-time PCR was experimentally determined to reach 30-50 target molecules, which is close to theoretical prediction. Starting PCR with 200 ng genomic plant DNA, the LOQ depends primarily on the genome size of the target plant and ranges from 0.02% for rice to 0.7% for wheat. The precision of quantitative PCR detection methods, expressed as relative standard deviation (RSD), varied from 10 to 30%. Using Bt176 corn containing test samples and applying Bt176 specific QC-PCR, mean values deviated from true values by -7to 18%, with an average of 2+/-10%. Ruggedness of real-time PCR detection methods was assessed in an interlaboratory study analyzing commercial, homogeneous food samples. Roundup Ready soybean DNA contents were determined in the range of 0.3 to 36%, relative to soybean DNA, with RSDs of about 25%. Taking the precision of quantitative PCR detection methods into account, suitable sample plans and sample sizes for GMO analysis are suggested. Because quantitative GMO detection methods measure GMO contents of samples in relation to reference material (calibrants), high priority must be given to international agreements and standardization on certified reference materials.

Ochratoxin A (OTA) in coffee: nation-wide evaluation of data collected by German Food Control 1995-1999

The evaluation process involved data collected by Official Food Control Laboratories during the period 1995 until 1999. A total of 613 samples analysed for ochratoxin A and complying with a detection limit lower than 0.6 microg/kg were evaluated. With the assistance of statistical process analysis the median concentrations for green coffee (0.4 microg/kg), for roasted coffee (0.6 microg/kg), for decaffeinated roasted coffee along with low-acid decaffeinated roasted coffee (0.4 microg/kg) as well as for soluble coffee (0.7 microg/kg) were determined. The result is a mean daily total intake per consumer of 9 ng OTA.

Einsatz der Instrumentalanalyse im Rahmen der amtlichen Lebensmittelüberwachung

Swiss legislation of food is enforced by the cantonal laboratories. Through inspection of the food companies and analysis of samples, they survey the conformity of the production and products. Within the last 15 years, the number of samples analysed has fallen by about 30%. The parameters to be analysed are numerous and need high sensitivity and selectivity. The equipment of the official laboratories enable these investigations to be performed well, but only a few labs are using certain crucial instrumental technologies, other methods are not implemented at all. Thanks to instrumental analytical methods, unsuspected frauds or unexpected contaminations can be revealed. This article gives an overview of the instrumental analysis methods used by the official foodcontrol laboratories with examples of applications. It also gives a perspective on how these expensive analytical ressources should be shared between the cantonal laboratories.