Total reflection X-ray fluorescence used to distinguish mechanically separated from non-mechanically separated meat

This paper presents the successful application of total reflection X-ray fluorescence spectroscopy (TXRF) for the identification of products obtained from mechanically separated meat (MSM), a very important issue for food quality and safety. According to the European Food Safety Authority, one of the most important parameters to distinguish MSM is the content of Ca. Consequently, the development of reliable and cost-effective analytical tools is very important to monitor the chemical composition of these foods. In this study, we have developed an analytical method for elemental analysis of meat samples based on total reflection X-ray fluorescence. A simple sample preparation by suspending the grinded meat sample in a solution of diluted Triton X-100 and polyvinyl alcohol in water showed to be the best for this kind of samples. Fresh chicken meat, chicken meat with different percentage of MSM, pure MSM and meat products prepared with MSM were analyzed. The content of K, Ca, Fe, Cu and Zn was determined. Results show that Ca, but also K and Fe are significant markers to distinguish MSM from fresh meat. A limit of 40% MSM for differentiation was achieved by applying principal component analysis. The method accuracy was evaluated comparing the obtained results with those obtained after acidic digestion and ICP-MS analysis.