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4340533394?profile=RESIZE_710xThe March 2020 Foods Journal has a special issue on “Food Authentication: Techniques, Trends and Emerging Approaches” consisting of  12 articles (11 original research articles and 1 review), which focus on the development and application of analytical techniques and emerging approaches in food authentication. The research papers cover the authentication of foods with high commercial value, such as olive oil, Iberian ham or fruits, among others. The review examines the potential of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) as a valuable technique to determine small metabolites in food tissue sections without requiring purification, extraction, separation or labelling. It can be used not only to identify the composition of foods, but also to investigate among other applications, their geographical origin for improved traceability, food safety and breed enhancement. 

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In our March 2020 Newsletter on page 8 there was a call for new Centres of Expertise. Originally, the closing date for proforma applications was the end of March. In view of the disruption caused by the Covid-19 situation, the deadline for new applications has been extended until the end of April. I would encourage any laboratory which is either specialist or general in authenticty methodology, especially with an agent or base in the UK, to consider applying.

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4274482663?profile=RESIZE_710xGas chromatography techniques are routinely used to detect key lipids (e.g., triacylglycerols) to assess milk origins and to detect foreign milks in bovine milk. However, such approach requires several sample preparation steps and a dedicated laboratory environment, precluding a high throughput process. In order to simplify sample preparation and speed of analysis, UK researchers developed a novel and simple method without organic solvent extractions for the detection of bovine and non-dairy milks based on lipids fingerprint by routine MALDI-TOF mass spectrometry. The method was tested using mixtures of bovine with either soya or coconut milks in the range of 0-100% additions. Marker ions specific to each type of milk permitted a reproducible and cost effective approach to milk analysis, which is suitable to qualitatively typify milks and potentially their adulteration.

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4273790207?profile=RESIZE_710xThis pilot study used SIRA (stable isotope ration analysis) and trace element analysis to verify the organic status of pork purchased in the markets from four different regions of China. Four stable isotope ratios (δ13C, δ15N, δ2H and δ18O) and the concentrations of seven elements (K, Na, Mg, Ca, Fe, Cu and Se) were determined in organic and conventional pork samples from the four locations of China. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to analyse stable isotope ratios and multi-element concentrations in pork. Discrimination between the organic and conventionally reared pigs was based mainly on δ15N as the marker for organic feedstuffs. Using the limited database of analytical values, the methodology would potentially be able to confirm whether a sample of pork came from the region and organic status it claimed. 

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4248572073?profile=RESIZE_710xThis study examines fraud vulnerability in the Dutch food service sector; identifies underlying fraud vulnerability factors; and studies the differences in fraud vulnerability between casual dining restaurants, fine dining restaurants and mass caterers for four product groups. Vulnerability was assessed by an adapted SSAFE food fraud vulnerability assessment, tailored to the food service sector. Fifteen food service operators were assessed, and were rated high vulnerability for 40% of the fraud indicators, which is much higher than food manufacturers, wholesalers and retailers assessed in a previous study. In particular, there was more opportunities for fraud and fewer controls were noted. The overall fraud vulnerability was determined more by the type of food service operator than by the type of food product. Hence casual dining restaurants were assessed as being the most vulnerable, followed by fine dining restaurants. Mass caterers were assesed as the least vulnerable operators to fraud, because they had more adequate controls in place.

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4248264363?profile=RESIZE_710xBecause of its higher price, goats milk is vulnerable to adulteration by cheaper cows milk. A rapid method based on β-carotene as a marker for cows milk, but absent in goats milk, has been developed using Raman and Infrared spectroscopy with chemometrics. The application of PLSR (partial least squares regression) to the two spectrocopic methods was the most successful giving an good correlation coefficient of validation (R2 value > 96) and an accurate determination of β-carotene content and percentage in spiked milk.

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4223202673?profile=RESIZE_710xTurmeric sales in the U.S. have increased dramatically over the last five years, from US$163 million in 2014 to US$375 million in 2019, which is also mirrored by a global increase as well. This increase in turmeric trade also gives an increased problem of adulteration and fraud. The article discusses with leading experts the potential and identified adulterants, and what consumers should do to protect themselves from purchasing adulterated turmeric.  

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4223074748?profile=RESIZE_710xThe content of the endosperm of the coconut (Cocos nucifera L.) contains “coconut water”. This practically sterile liquid, which is prized for its delicate, albeit labile, flavour when fresh, has had a recent dramatic increase in global demand. This review examines  the variances in natural composition, maturity, processing-induced compositional changes, adulterations, product recalls, classical and instrumental methods of analysis and on the available composition standards of coconut water. The review also makes recommendations on the analytical approaches to verifying the authenticty and determination of possible adulterants, but also given the variation of composition with maturity, that  a weight of evidence approach should be taken in the assessment of authenticity.

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4200987362?profile=RESIZE_710xA conceptual model for consumer trust in the food system relating social trust, beliefs in trustworthiness, overall trust in food chain actors (farmers, manufacturers, retailers and authorities), and confidence in both the supply of food products and food technologies, was developed and validated in 5 countries (Germany, France, Poland Spain and UK). The data were collected via an online survey in the 5 countries. Consumer confidence is largely determined by consumer beliefs about the trustworthiness of food chain actors. In particular the beliefs about openness, and especially about the openness of food manufacturers, are strongly related to consumer confidence. Consumer confidence and trust appears lowest in France and highest in the UK, although the differences are small.

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130790201?profile=RESIZE_710xNew figures from Italian farming organisation Coldiretti suggest the turnover of the 'agri-mafia' is now estimated at €24.5bn per year, affecting the entire food supply chain from farm to table. In an attempt to combat this organised criminal activity, the Italian Council of Ministers has approved new legislation that it says would help crack down on the country’s big problem with agriculture and food fraud. The bill introduced tougher criminal penalties for “agribusiness piracy” crimes, such as selling products as made in Italy when they are not, falsely claiming foods are organic or outright counterfeiting. The new penalties apply to those who “produce, transform, package, distribute, sell or profit from” fraudulent agricultural products such as extra virgin olive oil. 

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4167366632?profile=RESIZE_710xA pilot programme is applying blockchain to Australia's Victoria’s citrus production, which exported 104,000 tonnes during the 2018/19 season, worth A$162m. The long-term goal is to apply the technology to all Australian citrus exports. The pilot programme is funded by Agriculture Victoria, and will aim to improve a number of key factors, including determining the fruit’s origin, protection against counterfeiting, location of origin, secure market access and rapid food recalls.  Read the article here 

For a more general discussion about how blockchain can assist in ensuring the authenticity of foods read this article.

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4167177917?profile=RESIZE_710xThe common cuttlefish (Sepia officinalis) is highly appreciated by consumers, and Spanish reseachers have developed a rapid assay to determine its authenticity. The method  is based on TaqMan real-time PCR (Polymerase Chain Reaction) method to amplify a 122 base pairs (bp) fragment of the mitochondrial COI (Cytochrome Oxidase I) region. Reference and commercial samples of S. officinalis showed a threshold cycle (Ct) mean of 14.40, while the rest of the species examined did not amplify. No cross-reactivity was detected with any other species. The assay differentiates S. officinalis from other species of the genus Sepia and other cephalopod species, and works for fresh, frozen, grilled, cooked and canned samples of Sepia spp. 

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4159170239?profile=RESIZE_710xThe official AOAC method for  the detection of C4 derived exogenous sugars, such as cane sugar or high fructose corn syrup, in honey is based on stable-isotope ratio mass spectrometry analysis of δ13C value of honey versus δ13C of honey protein. However, this method gives false positives with certain Australian honeys, especially those from the Leptospermum species such as Manuka honey. Australian researchers have improved the method, which not only determines the isotopic values of “proteins” precipitated using the standard AOAC method, but also “proteins” precipitated after incorporation of a further modification step, which removes insoluble material (including pollen) from the honey before precipitation. The modified method includes the analysis of different isotopes of the precipitated protein, sugar profiles and Manuka markers. This new method will detect residual sugar feeding of bees, as well as the adulteration of honey with C4 sugar.

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4156897705?profile=RESIZE_710xIn a first for food authentication, German researchers have developed a new CRISPR/Cas9 based in vitro assay to distinguish a fine cocoa variety from a bulk cocoa variety. Ecuador is a major supplier of a fine single cocoa Variety Nacional (Arriba), but also produces a cheaper but less aromatic bulk cocoa “Colección Castro Naranjal 51” (CCN-51).  There are several characteristic SNPs (single nucleotide polymorphisms) that could be used to distinguish these two varieties. However, the detection of single base exchanges in order to differentiate raw material types or varieties is challenging, as some of the methods require the use of restriction endonucleases. The use of the programmable Cas9 endonuclease known from the genome editing system CRISPR/Cas9 is a powerful alternative. The detection of bulk cocoa in fine cocoa uses a SNP which is located within a PAM region (protospacer adjacent motif) mandatory for the Cas9 endonuclease. Consequently, only the bulk cocoa is attacked by the nuclease. The result can be recorded using agarose or capillary gel electrophoresis (AGE and CGE). Both methods yielded comparable results. AGE can be used for a semi-quantitative estimation and the more sophisticated CGE for quantitation based on a calibration line. The assay could reliably detect 10% CCN-51in an admixture with Arriba, which is a realistic level for routine applications.

This approach could be adapted to other authenticty applications which use SNPs for variety or species identification. Read the abstract here

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The True Cost of Illicit Fisheries

4144311116?profile=RESIZE_710xA research paper has just been published outlining the true cost of illegal, unreported and unregulated fisheries around the world on 143 countries. The paper estimates that the annual magnitude of the unregulated, illicit trade in marine fish catch globally is between 8 and 14 million metric tons,   suggesting gross revenues of US$9 - 17 billion associated with these catches. The estimated loss in annual economic impact due to the diversion of fish from the legitimate trade system is estimated at US$26 - 50 billion, while losses to countries’ tax revenues are between US$2 - 4 billion. This trade is having a disproportionat impact on the nutritional status and economic wellbeing of countries in Africa, Asia and South America in particular. This trade is mostly carried out by a large factory ships, which take the fish overseas without unloading or processing in the fishing ground host countries, thereby depriving local economies of tax, income, and jobs, and leading to depletion of the regions fish stocks.

Read the article here or the full research paper

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A New Method for Exogenous Sugar Detection

4115428087?profile=RESIZE_710xSugar adulteration using carbon isotope ratio analysis by mass spectrometry is well established, but it can only be used for C4 sugar (from cane or maize) adulteration. Although a method has been developed to determine C3 sugar (from beet, most fruits or wheat) adulteration using hydrogen/deuterium isotope ratio analysis by mass spectrometry, it requires very time consuming chemical derivative preparation. The established method for C3 sugar determination has been quantitative deuterium nuclear magnetic resonance (2H NMR) measurement of ethanol derived from the sugars in the sample, which again is time consuming, and requires a normalisation process to compensate for the deuterium content of the fermentation water. Researchers at IAEA have developed a rapid method for both C3 and C4 sugar detection, which derivatises the carbohydrate's exchangeable hydroxyl-hydrogens, so that the derivative compound is sufficiently volatile to be separated and measured by a gas chromatograph coupled to an isotope ratio mass spectrometer. Feasibility of the method has been shown by measuring sugars from fruit juice and honey, but further work is required to assess the reproducibility of this method and establish its applicability for detection of undeclared addition of exogenous sugars and syrups to a range of other foods and beverages.  .

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4016991159?profile=RESIZE_710xδ15N has been used to distinguish organic from conventionally grown tomatoes for some time, but is not consistent. This paper describes an improvement on the δ15N SIRA method to authenticate organic tomatoes by undertaking the15N/14N analysis on the extracted amino acids. A gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) based method was developed, and analysis of C and N isotope ratios of amino acids taken along the passata production derived from tomatoes grown in two Italian regions over two years. δ15N was the most significant parameter for discriminating organic from conventional products, but the classification power was improved significantly by compound-specific (amino acids) isotope analysis regardless of the production years and regions. 

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The Food Authenticity Network Newsletter for March 2020 is now available on the website. It has three interesting articles: 

  • Professor Elliott describes a large EU/China Ministry of Science and Technology project EU-China Safe.
  • How Australia has approached maintaining the authenticity of Extra Virgin Olive Oil.
  • A new system of detecting fraud in the supply chain ‘Check Integrity’ using mass balancing.

Also, there is an update on the activities of the Network, and the changes in the organisation of the Network as we move from a UK based to a global network, and a call for new Centres of Expertise to register on the website.

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4015149034?profile=RESIZE_710xTurmeric is a spice highly valued for its colouring properties, but increasingly for its medicinal properties. India is the largest producer, and the review details the artificial colourants and bulking agents that have been used to adulterate turmeric, and the methods used to identify and measure them. The review also details the DNA methods for identifying other plant adulterants and authenticating tumeric.

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3823828176?profile=RESIZE_710xGreek researchers have evaluated using DNA markers SNPs (single nucleotide polymorphism) and SSRs (simple sequence repeats) combined with high resolution melting (HRM) to authenticate monvarietal olive oils and the quantitative determination of adulteration with other plant oils (maize and sunflower oils). The SSR-HRM was more efficient in distinguishing monovarietal olive oils, while the SNP-HRM assay was more reliable in discriminating olive oil blends. HRM was also used for the detection of adulteration of olive oil with oils of different plant origin by using plastid trnL indels and SNPs. The trnL-indels-HRM showed higher discrimination power than the trnL-SNP-HRM in determining adulteration in olive oil. 

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