L-Methionine

L-Methionine Item Specification Appearance White crystals or crystalline powder Specific Rotation[α]D20 +23.0° to +24.5° State of solution Clear and colorless Not less than 98.0% Chloride (Cl) Not more than 0.020% Ammonium (NH4) Not more than 0.02% Sulfate (SO4) Not more than 0.020% Iron (Fe) Not more than 10ppm Heavy Metals (Pb) Not more than 10ppm Aresenic (As2O3) Not more than 1ppm Other amino aicds Chromatographically not detectable Loss on drying Not more than 0.20% Residue on ignition Not more than 0.10% Assay 99.0% to 100.5% pH 5.6 to 6.1