The treatment of rapeseed meal and its effect on chemical composition and egg tainting potential

Treatment of high glucosinolate Brassica napus meals with lime, ammonia or by micronisation lowered their tainting potential by reducing their progoitrin, soluble tannin and sinapine contents. These effects were not sufficient to prevent inhibition of trimethylamine oxidation and the consequent rise in egg trimethylamine levels above the tainting threshold when the meals were fed to susceptible hens as sources of protein (100 g kg−1 diets).