As pineaple has a CAM (crassulacean acid) metabolism, the carbon 12/13 ratios for pineaple lie between those for C3 and C4 plants making the use of carbon isotope ratio detection of exogenous sugars very challenging. The detection of beet (C3) and (C4) cane and maize based sugar adulteration of pineapple juice has not even been possible using site specific deuterium/hydrogen ratios (2H/1H) by quantitative deuterium nuclear magnetic resonance (SNIF-NMR) of the ethanol fermented from the pineapple juice sugars because of changes during the fermentation. IAEA scientists have developed a new GC-IRMS-based stable hydrogen isotope method, which utilises the trifluoroacetate derivative of sucrose to allow direct measurement of the carbon-bound non-exchangeable hydrogen. This provides advantages over alternative isotopic methods in terms of analysis time and sensitivity. This feasibility study has demonstrated the potential to reliably differentiate between authentic pineapple juices and those adulterated with commercial beet and cane sucrose.

Read the full open access paper here

A Ph.D thesis from the University of Milan-Bicocca in English is publicly available. The thesis gives a good overview of DNA barcoding, NGS (Next Generation Sequencing) and metabarcoding, and isothermal nucleic acid amplification. The research carried out looked at applying DNA barcoding to processed foods, which required smaller DNA fragments. However, the approach is not suitable for mixed species samples, and NGS and metabarcoding approaches were more successful. Finally, an isothermal amplification assay was applied to authenticate truffles.

You can read the 253 page thesis here   

This book highlights the use of specific physicochemical parameters, such as sugar content, moisture content, electrical conductivity, acidity, colour, and attributes in the production of honey. It also discusses the use of honey micro-constituents, including volatile compounds, polyphenols, minerals, organic acids, free amino acids and isotopic data, in the determination of the botanical and geographical origins of honey, in combination with chemometrics. It represents the ultimate research guide and reference manual for the determination of honey uniqueness. 

More information on the content here

Lloyds Register surveyed senior executive across the global beverage sector about their supply chain issues and experience of fraud. Of those completing the survey, 97% had been affected by fraud in the past 12 months, and 80% agreed that fraud was a growing concern. Sixty three percent of the respondents were inthe alcoholic beverage sector and 37% in the non-alcoholic sector. When asked to identify the single biggest fraud threat to their business, the respondents were split almost equally between counterfeiting (32%), adulteration (30%) and simulation (designing a product to look very similar to the legitimate product) (30%). 

You can read the reaction of the dairy sector to the report here. The Lloyds Register Report is free, but you have to register to obtain it. 

The  development of rapid non-destructive hand held devices for testing for food authenticity has been growing at a pace in recent years. US researchers have developed the MasSpec Pen technology, which is placed on the food and connects with a mass spectrometer that employs a solvent droplet and gives an answer in 15 seconds.The MasSpec Pen has been used to authenticate grain-fed beef, grass-fed beef, venison, cod, halibut, Atlantic salmon, sockeye salmon, and steelhead trout. Statistical models developed with the Lasso method using a training set of samples yielded per-sample accuracies of 95% for the beef model, 100% for the beef versus venison model, and 84% for the multiclass fish model. In addition, feasibility testing for classifying venison and grass-fed beef samples adulterated with grain-fed beef achieved prediction accuracies of 100% for both classifiers using test sets of samples.

Read the abstract here

This report from the Norwegian Research Institute Nofima, and one of the research outputs of the EU Project EU-China Safe, examines the supply chain from the Bordeaux region in France to China to try and identify where discrepancies in the recorded traceability data and points of weakness might occur in order to indicate vulnerability to possible fraud. The mapping and analysis of the supply chain, and the indication of where fraud might happen was partly based on existing scientific literature, reports, and news stories, and partly on a number of interviews conducted with supply chain actors in France and in China. The limitations of this report relate to the fact that the study has focused solely on the Bordeaux wine trade between France and China. Access to respondents for the study was limited, even if the data collected was complemented with both primary and secondary data sources. Because the wine supply trade is quite complex, it is acknowledged that there are many more perspectives along the local-in-global supply chain that have not been reflected in this report. However, this study will contribute to the growing body of academic literature and discussion to inform governance structures for the cultivation of a more secure food trade and traceability between Europe and China in general. 

Read the full report here

Sanger sequencing (DNA barcoding) is a robust method for species identification. However, it is not always suitable for species identification of processd mixed species products. Chinese researchers have developed an NGS method based on the amplification and sequencing of shorter 16S rRNA DNA sequences. The assay was developed using a mixture of 8 salmon species, which were all correctly identified even when the species was presented as low as 1%(w/w). It was tested with a market survey of 32 commercial salmon products. Sanger sequencing was used on single species unprocessed products and NGS on mixed species products, which was also cross validated with a real-time PCR assay. The survey revealed that 50% of the samples were mislabelled.

Read the abstract here. 

Honey is regarded as one of the foods most susceptible to adulteration or mislabelling. Greek researchers have used the Scopus database to determine which issues and methods of authenticity have had most published papers. The result indicated that the determination of botanical origin  was the most studied authenticity issue, and chromatographic methods were the most frequently used for its assessment. This comprehensive review examines other methodologies to assess honey botanical and geographical origin using separation techniques, DNA methods, spectroscopic, elemental and isotopic techniques. Methods for sugar adulteration of honey are not covered.

Read the full open access paper here

Coffee leaf rust (Hemileia vastatrix) has decimated coffee regions around the world, and now it has reached Hawaii's Kona coffee region. If farmers find rust before it is on more than 5 percent of the coffee leaves on their farms, then it can be controlled by spraying preventative fungicides made with copper and bacillus, a bacteria found in soil. If the infected leaves are more than 5% infection, then the disease spreads quickly.

Read the article here

Recent cases show that herbs and spices are susceptible to adulteration. Italian researchers have utilised AMS (ambient mass pectrometry) coupled to mid-level data fusion as a rapid non-targeted method for oregano authentication for the first time. Authentic and adulterated oregano samples were extracted using two procedures and analysed in positive and negative ion modes by direct analysis in real time-high resolution mass spectrometry (DART-HRMS). The four blocs of data were combined into a unique dataset and analysed chemometrically to distinguish authentic from adulterated oregano.  Fourteen most informative signals of authenticity were chosen and validated. The final model gave an accuracy, sensitivity and specificity of >90%.  

Read the abstract here

In 2019, a Europol-coordinated operation resulted in the seizure of 150,000 litres of low-quality oils that had been adulterated with colourants to make them appear like extra virgin olive oils, with 20 arrest made. There are recommended methods to authenticate olive oils using different test procedures applied one after the other, which is time-consuming and expensive. German researchers have developed a rapid NMR (nuclear magnetic resonance) that gives a  profile based on the identification of constituents such as fatty acids and polyphenols in one hour. A database of profiles has been built up with extra virgin olive oil produced in Greece, Italy and Spain permitting the country of origin to be checked as well.

Read the article here

DNA authentication of wines is challenging given the acidic and alcoholic medium of wines coupled with their long storage. Russian researchers have investigated using the centrifuged debris precipitated from either red or white wines using various precipitators and co-precipitators as a source of DNA for grape varietal identification. The strategy for identification was based on direct sequencing of the PCR (polymerase chain reaction) products amplified using primers based on the grape UFGT gene locus. Although DNA extracted directly from grape varieties gave good varietal identification, there were some problems in identifcation encountered in analysing commercial wines, which indicated further research is necessary for method improvement. 

Read the open access paper here

In the European Commission's Farm to Fork Strategy document, there is an initiative to consider extending the country of origin provisions in the Food Information to Consumer Regulation to more foods in Q4 of 2022. At present, there is obligatory origin labelling for  fruits and vegetables, olive oil, honey, eggs, meat, fish, wine and spirit drinks. The categories of foods suggested for an extended country of origin labelling are milk, rice, and potatoes, but some Member States want it to be applied to all foods.

Read the article here

The Guardian newspaper has made a study of 44 reports in over 30 countries of the labelling of 9,000 fish and seafood samples in catering and retail, which reveal that around 36% were mislabelled. The fish and seafood most susceptible to mislabelling were snapper, king scallops, and shark.  

Read the article here

This review investigates the feasibility of different non-destructive techniques used for authenticating meat products, which could provide real-time monitoring in the near future. The spectroscopic techniques reviewed are NIR (near infrared), MIR (mid-infrared), FTIR (Fourier transform infrared), and Raman. The imaging techniques discussed are colour imaging, hyperspectral imaging and Xray imaging with computed technology. The advantages of these techniques is that they can be applied in-situ, and they give rapid results, but calibration procedures are laborious. In addition, the results are influenced by scanning times, sample to detector distance and environmental factors such as ambient temperature, humidity, illumination conditions, and sample temperature, the latter can differ in meat processing facilities. However, it is hoped that the application of these techniques will be easier with the improvement in instrumental technology, the availability of high-speed computers with appropriate storage capacity, and the development of appropriate chemometric procedures.

Read the full paper here

Aromatic peanut (groundnut) oil (APO) is produced from roasted peanuts, and hence has stronger peanut aroma than refined peanut oil. It is popular in Chinese, Indian and SE Asian cuisine. Chinese researchers determined the tocopherol content of APO and 4 refined vegetable oils (soybean, sunflower, maize, and rapeseed oils) using hplc with UV detection. The tocopherol isomer content, especially α and γ tocopherols, were found to be the most suitable markers to disciminate between APO and the 4 vegetable oils. In addition, APO was mixed with the 4 oils (at the levels of 5, 10, 15, 20 and 25 g/100 g, w/w) to determine whether the tocopherol analysis is a better approach than fatty acid profiling for detecting APO adulteration. The results showed that for tocopherols, the detection limits were 5 g/100 g for soybean oil and 10 g/100 g for other three oils in APO, showing a higher sensitivity than fatty acids profile based method for detecting APO adulteration.  

Read the abstract here

The International Hologram Manufacturers Association (IHMA) claim that a new development of edible holograms could help food integrity and prevent fraud. This follows a report that US scientists have been able to embed edible holograms into chocolate. These are made from a thin film of a dried solution of glucose syrup, vanilla and water, which is coated with a fine layer of non-toxic black dye. The dye is etched off using direct laser interference patterning, leaving raised nanoscale lines, which act as a diffraction grating and produces the image or information visible on the hologram. Whilst the development only works for certain types confectionery, it has opened up a host of opportunities and innovations in the control and labelling of food.

Read the article here

Crustaceans are high value foods with a high incidence of species substitution. German researchers have developed a multiplex RT-PCR (real-time polymerase chain reaction) assay to identify four important commercial crustaceans - giant tiger prawn (Penaeus monodon), whiteleg shrimp (Litopenaeus vannamei), Argentine red shrimp (Pleoticus muelleri), and Dublin Bay prawn or scampi (Nephrops norvegicus). The specificity of the assay was confirmed by testing more than 30 crustacean species, and the performance of the method was evaluated with varyingly processed crustaceans, as well as with commonly used spices and herbs. 

Read the abstract here

Italian researchers have developed a novel assay for DNA sensing of genetically modified (GM) soya based on the use of magnetic microbeads functionalised with PNA (peptide nucleic acid) probes and a subsequent read-out on screen-printed electrode (SPE) substrates. The PNA probes bind to a complementary DNA target extracted from non-amplified genomic DNA from GM Roundup Ready soya. The microbeads are then separated using a magnet and visualised on the screen to enable discrimination between the GM and the non-GM soya. The method was validated by comparing the results to other DNA assays requiring preliminary amplification of target DNA via PCR (polymerase chain reaction).

The ability of the magnet bead assay to detect the presence of Roundup Ready soya DNA sequence was tested on genomic DNA extracts from European Reference Material soya flours, demonstrating the capability of the method to match the European Union regulation for labelling of food containing a percentage of GM products greater than 0,9%.

Read the abstract here

The European Commission's Joint Research Centre (JRC) has published its January 2021 Food Fraud Monthly Summary reporting food fraud incidents and investigations from around the world. Thanks again to our Member Bruno Séchet for creating this  infographic and allowing us to share it with the rest of the Network

Read the January 2021 Summary here