Goitom Asfaha D.,European Commission |
Quetel C.R.,European Commission |
Thomas F.,Eurofins |
Horacek M.,AIT Austrian Institute of Technology |
And 24 more authors.
Journal of Cereal Science | Year: 2011
The aim of this work (from the FP6 project TRACE) was to develop methods based on the use of geochemical markers for the authentication of the geographical origin of cereal samples in Europe (cf. EC regulations 2081/92 and 1898/06). For the first time, the potential usefulness of combining n(87Sr)/n(86Sr) and δ13C, δ15N, δ18O and δ34S isotopic signatures, alone or with key element concentrations ([Na], [K], [Ca], [Cu] and [Rb], progressively identified out of 31 sets of results), was investigated through multiple step multivariate statistics for more than 500 cereal samples collected over 2 years from 17 sampling sites across Europe representing an extensive range of geographical and environmental characteristics. From the classification categories compared (north/south; proximity to the Atlantic Ocean/to the Mediterranean Sea/to else; bed rock geologies) the first two were the most efficient (particularly with the ten variables selected together). In some instances element concentrations made a greater impact than the isotopic tracers. Validation of models included external prediction tests on 20% of the data randomly selected and, rarely done, a study on the robustness of these multivariate data treatments to uncertainties on measurement results. With the models tested it was possible to individualise 15 of the sampling sites. © 2010 Elsevier Ltd.
Rummel S.,BSPG Bayerische Staatssammlung fur Palaontologie und Geologie |
Dekant C.H.,BSPG Bayerische Staatssammlung fur Palaontologie und Geologie |
Holzl S.,BSPG Bayerische Staatssammlung fur Palaontologie und Geologie |
Holzl S.,GeoBio Center |
And 10 more authors.
Analytical and Bioanalytical Chemistry | Year: 2012
The strontium isotope ratio ( 87Sr/ 86Sr) in beef, derived from 206 European cattle, has been measured. These cattle were located in 12 different European regions within France, Germany, Greece, Ireland, Italy, Spain and the UK. As animal protein is known to be a difficult material on which to conduct Sr isotope analysis, several investigations were undertaken to develop and improve the sample preparation procedure. For example, Sr isotope analysis was performed directly on freeze-dried meat and defatted dry mass from the same samples. It was found that enormous differences-sometimes exceeding the measurement uncertainty-could occur between the fractions and also within one sample even if treated in the same manner. These variations cannot be definitely allocated to one cause but are most likely due to inhomogeneities caused by physiological and biochemical processes in the animals as post mortem contamination during analytical processing could be excluded. For further Sr isotope measurements in meat, careful data handling is recommended, and for the authentic beef samples within this project, it was decided to use only freeze-dried material. It can be demonstrated, however, that Sr isotope measurements in beef proteins are a valuable tool for authentication of geographic origin. Although partly overlapping, some of the European sampling sites could be discriminated even by only using 87Sr/ 86Sr. [Figure not available: see fulltext.] © 2012 Springer-Verlag.