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Collagen-based chicken skin is being increasingly used in fat reduced meat products as it has good water retaining properties. This study has identified two unique peptide markers of chicken skin collagen, after extraction, and trypsin digest using LC-MS. The assay has very low detection limits for the two peptide markers. The method was validated by analysing the peptides derived from pork and beef collagen in meat and collagen mixtures. The two chicken collagen peptide markers were not found in either beef or pork collagen, and hence were unique to chicken skin. Further work to make the method quantitative is being undertaken.

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Screening assays, for example, lateral flow assays (LFAs), can improve traceability, but often lack the required reliability. This paper gives an alternative approach for secure on-site compliance testing, using allergens as a case study. As a screening assay, a smartphone raw image analysis of the LFA gives an initial quantification of the proteins separated in the LFA . The proteins are then extracted from the LFA, and analysed by LC-MS (liquid chromatography-mass spectrometry) to quantify them more accurately. This approach was applied successfully to the allergenic proteins in peanuts and gluten.  

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Adulteration of meat products using offal is one of the routes of fraud. This paper describes a method developed to detect the presence of pork liver by identifying specific peptide markers from its trypsin digest using  liquid chromatography-mass spectrometry. Although 74 specific peptides were initially identified from thermally processed pork liver, after examining peptides derived from heat processed pate-type products, five specific peptides were chosen as authenticity markers to confirm the presence of pork liver in highly processed meat products.  

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This mini-review examines the use of liquid chromatography mass spectrometry (LC-MS)-based metabolomic and lipidomic methodology to determine metabolites and lipids in pork and beef, which combined with chemometric analysis and comparison with lipid and metabolite databases, serve as authenticity markers. Researchers in this field have found combining metabolomic and lipidomic approaches provides a more comprehensive authentication of meat products especially the differentiation between beef and pork. 

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Metabolic markers are considered as a promising choice for food authentication, but few metabolic markers were available to develop robust analytical methods for food authentication in routine control. Untargeted metabolomics by liquid chromatography-mass spectrometry (LC-MS) is increasingly used to discover new metabolic markers. This review summarises the general workflow, recent applications, advantages, limitations, and future needs of untargeted metabolomics by LC-MS for identifying metabolic markers. It concludes that untargeted metabolomics by LC-MS shows great efficiency to discover the metabolic markers for the authenticity assessment of biological identity, geographical origin, agricultural production, processing technology, freshness, and cause of animals’ death.

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Olive oil, especially extra virgin oilive oil (EVOO), is highly valued for its organoleptic and nutritional qualities. In this study, more than 200 monovarietal (Koroneiki) EVOO samples were collected from the main Greek olive oil producing regions. They were analysed using Flow Injection Analysis-Magnetic Resonance Mass Spectrometry (FIA-MRMS), which directly injects the oil into the mass spectrometer, to determine a metabolite profile. In parallel, the same oils were analysed using an LC-Orbitrap MS (Liquid Chromatograpy-Mass Spectrometry) platform to verify the efficiency of the method, as well as a tool to increase the identification confidence of the proposed markers.  The results obtained by FIA-MRMS analysis generated improved projection and prediction models in comparison to those of the more established LC-MS methodology. Also with FIA-MRMS, more statistically significant compounds and chemical classes were identified as quality and authenticity markers, which were associated with specific authenticity issues, i.e. geographical region, cultivation practice, and production procedures. 

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German and Italian researchers have used a proteomics based assay to distinguish wild from farmed salmon. A total of 13 farmed and 13 wild Canadian salmon (Salmo salar) species were extracted and digested with trypsin. The peptide digest was analysed by an optimised LC- MS system(quadrupole time-of-flight mass spectrometer) followed by statistical analysis based on principal component (PC) analysis.This untargeted approach, using a data-independent acquisition MS scheme, demonstrated the ability to effectively discriminate salmon belonging to the two classes. Furthermore, selected peptides showing high loadings on PC1 could represent potential targeted candidate peptide markers able to discriminate farmed from wild-type salmon.

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Coffee is currently the second largest commodity on the world market. Brazilian researchers have written a comprehensive review on the development and use of chromatograpy from paper to gas and hplc, and finally ultra-performance liquid chromatography coupled with tandem mass spectrometry to confirm adulteration and fraud in coffee.  

 Read the full review here