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Chinese researchers have developed a method for the rapid visual detection of adulterated meat based on both the lateral flow strip (LFS) platform and on polymerase chain reaction (PCR). After the rapid extraction of genomic components from meat, the on-site amplification of the target DNA of  duck meat is carried out with the rationally designed functional FITC- and biotin-modified primer set, thereby producing numerous double-stranded DNA  products dually labelled with FITC and biotin. The FITC-labelled terminal end of the products binds to the pre-immobilized FITC antibody on the test line of the strip, and the biotin-labelled terminal end binds to the streptavidin-conjugated gold nanoparticles, resulting in a visible test line on the LFS for the rapid identification of duck meat in adulterated beef. After optimization, an adulteration ratio as low as 0.05% can be easily measured. Twenty two commercial processed meat samples were tested with this new method, and 4 adulterated samples were successfully identified by both the routine PCR method and the new LFS method. The LFS method is simple in design, convenient in operation, and can be easily extended to the identification of other adulterating meat species just by replacing the modified primers. 

 Read the abstract here

Example of a lateral flow strip for target DNA detection

This study evaluated the application of relative quantification of unique heat-stable species specific peptides in highly processed meat proteins. Using nano-LC-QTOF-MS/MS, 20 new, heat-stable peptide markers unique to chicken, duck and goose were identified. The method enabled detection of 1% (w/w) of chicken and 1% (w/w) pork in a mixture of the meat of three species, as well as 0.8% (w/w) beef proteins in commercial poultry frankfurters. This method includes a correction factor for each protein, based on the peptide MS detection probabilities, which are influenced by the physicochemical properties of the peptide. Considerable differences in abundance of myofibrillar and sarcoplasmic proteins were observed between samples and illegal proportions of ingredients were discovered.

Read the abstract at: Meat species quantification using peptide markers

A rapid multiple reaction monitoring (MRM) mass spectrometric method for the detection and relative quantitation of the adulteration of meat with that of an undeclared species is presented by IFR's Analytical Sciences Unit. The approach uses corresponding proteins from the different species under investigation and corresponding peptides from those proteins, or CPCP. Selected peptide markers can be used for species detection. The use of ratios of MRM transition peak areas for corresponding peptides is proposed for relative quantitation. The approach is introduced by use of myoglobin from four meats: beef, pork, horse and lamb. Focusing in the present work on species identification, by use of predictive tools, peptide markers were determined that allow the identification of all four meats and detection of one meat added to another at levels of 1% (w/w). Candidate corresponding peptide pairs to be used for the relative quantification of one meat added to another have been observed. Preliminary quantitation data presented here are encouraging.

Read the full article in Anal. Chem., 2015, 87 (20), pp 10315–10322  at: 

http://pubs.acs.org/doi/abs/10.1021%2Facs.analchem.5b02318