Is authentication of the geographic origin of poultry meat and dried beef improved by combining multiple trace element and oxygen isotope analysis?

Data available on contents of up to 72 different trace elements and the oxygen isotope ratio of 78 poultry breast and 74 dried beef samples were analysed to determine whether the accuracy of the prediction of the geographic origin is improved by combining promising methods. Validation was performed by determining the origin of a smaller sub-group using a statistical model established from the data of the second, larger, sub-group. As expected, the combined data proved useful for the determination of the geographic origin of meat samples. However, combining data did not clearly reduce the percentage of incorrectly classified individual samples compared to the two approaches applied separately. In poultry, cross-validation and validation resulted in 83% and 50% correct classifications, respectively. The corresponding values in dried beef were 73% and 43%. In conclusion, compared to element signature data alone, combining both methods did not improve predictions of origin. (C) 2008 Elsevier Ltd. All rights reserved.