Near-infrared reflectance spectroscopy enables the fast and accurate prediction of the essential amino acid contents in soy, rapeseed meal, sunflowermeal, peas, fishmeal, meat meal products, and poultry meal

Near-infrared reflectance spectroscopy (NIRS) calibrations were developed t o enable the accurate and fast prediction of the total contents of methioni ne, cystine, lysine, threonine, tryptophan, and other essential amino acids , protein, and moisture in the most important protein-rich feed ingredients . More than 1000 samples of global origin collected over four years were an alyzed on amino acids following the official methods of the United States a nd the European Union. Detailed data and graphics are given to characterize the obtained calibration equations. NIRS was validated with independent sa mples for soy and meat meal products and compared to the amino acid predict ions using linear crude protein regressions. With a few exceptions, validat ion showed that 85-98% of the amino acid variance in the samples could be e xplained using NIRS. NIRS predictions compared to reference results agree e xcellently, with relative mean deviations below 5%. Especially for meat and poultry meals, NIRS can predict amino acids much better than crude protein regressions. By enabling the amino acid analysis of many samples to be com pleted in a short time, NIRS can improve the accuracy of feed formulation a nd thus the quality and production costs of mixed feeds.