Division 6.7.2

Check that the digestion procedure is sufficient to release all the protein nitrogen by using a test portion of 0,20 g of pure tryptophan, 0,35 g of phenacetin or 0,20 g of lysine hydrochloride (4.10.). All weighings should be to the nearest 0,001 g. At least 98—99% of the nitrogen should be recovered.