This study looked at verification of egg production method from organic, free range, barn and caged produced eggs, all of which are defined in EU legislation. A total of 84 eggs were bought from local supermarkets in northern Spain (18 each of organic and free range eggs, and 24 each of barn and caged eggs). The egg contents were homogenised and centrifuged to separate the plasma from the granules, and the UV-VIS-NIR spectra of the plasma measured in a spectrophotometer, and different chemometric models applied to the spectra variables . As two samples were detected as outliers and removed, the 82 samples were divided into two groups: 62 for model calibration and 20 for validation. Spectra analysis with QDA (quadratic discriminant analysis) gave a higher accurate categorisation of the four production systems, with a sensitivity of 100% in the calibration set. The validation set scored 87.5% sensitivity and 94.07% specificity using the visible spectra.
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