DL-Methionine                           99.0%~101.0%                                  99.2%

Identification

Standardization

Result

Aspect

white crystallinepowder or small flakes

Complied

Identification

Infrared absorption

Chromatograms obtained in the test for related substances.

Optical rotation

A deep- red colour develops

Complied

State of solution

Clear and colorless

Complied

Loss on drying

0.5% max.

0.26%

Sulphated ash

0.1% max

0.05%

Heavy metals

20ppm max.

Complied

Chlorides

200ppm max.

Complied

Sulphates

200ppm max.

Complied

Related substances

Not more intense than thespot with referencesolution (0.2%)

Complied

PH value

5.4~6.1

5.6