Detection and Quantification of Ruminant Meal in Processed Animal Proteins: A Comparative Study of near Infrared Spectroscopy and near Infrared Chemical Imaging

This study compared the performance of single-point near infrared spectroscopy (NIR) and near infrared chemical imaging (NIR-CI) for the detection and quantification of ruminant meat meal in processed animal proteins (PAPs). A set of 126 fish-meal samples adulterated with controlled amounts (0.25% to 16%) of ruminant meal were analysed using the two techniques. Comparison of results showed that spectra obtained by NIR-CI provided better qualitative information, whereas more accurate quantitative predictions were obtained using NIR spectroscopy. NIR-CI thus offers greater potential for species discrimination/identification, whilst NIR spectroscopy is better suited for the quantification of meal derived from a given species in PAPs. These findings represent a first step in the analysis of mixed-species processed animal proteins and suggest that NIR-CI, by providing valuable information on species origin, is a promising tool that could be used as part of the EU feed control programme aimed at eradicating and preventing Bovine Spongiform Encephalopathy (BSE) and related diseases.