(mon'' oh soe' dee um gloo' ta mate).
Monosodium Glutamate contains NLT 99.0% and NMT 100.5% of C5H8NNaO4·H2O.
Sample solution: 1 in 30
Analysis: To 1 mL of the Sample solution add 1 mL of ninhydrin TS and 100 mg of sodium acetate, and heat in a boiling water bath for 10 min.
Acceptance criteria: An intense, violet blue color is formed.
Sample solution: 1 in 10
Analysis: To 10 mL of the Sample solution add 5.6 mL of 1 N hydrochloric acid.
Acceptance criteria: A white, crystalline precipitate of glutamic acid is formed on standing. Precipitation is promoted by agitation. When 6 mL of 1 N hydrochloric acid is added to the turbid solution, the glutamic acid dissolves on stirring.
• C. Identification TestsGeneral, Sodium 191: It meets the requirements of the pyroantimonate precipitate test.
Sample: 250 mg
(See Titrimetry 541.)
Mode: Direct titration
Titrant: 0.1 N perchloric acid VS
Blank: 100 mL of glacial acetic acid with a few drops of water
Endpoint detection: Potentiometric
Analysis: Wet the Sample with a few drops of water. Dissolve in 100 mL of glacial acetic acid. Titrate with 0.1 N perchloric acid VS. Perform a blank determination.
Calculate the percentage of monosodium glutamate (C5H8NNaO4·H2O) in the Sample taken:
Result = [(V B) × N × F × 100]/W
Acceptance criteria: 99.0%100.5%
• Chloride and Sulfate, Chloride 221: A 280-mg portion shows no more chloride than corresponds to 1.0 mL of 0.020 N hydrochloric acid (0.25%).
• Lead 251: NMT 10 ppm
• Heavy Metals, Method II 231: NMT 20 ppm
• Clarity and Color of Solution
Sample solution: 1.0 g in 10 mL of water
Standard solution: To 0.2 mL of a solution of sodium chloride containing 10 µg/mL of chloride ion (Cl), add 20 mL of water, and mix. Then add 1 mL of 5 N nitric acid, 0.2 mL of dextrin solution (1 in 50), and 1 mL of silver nitrate TS, and allow to stand for 15 min.
Analysis: Compare the Sample solution with the Standard solution (see Spectrophotometry and Light-ScatteringVisual Comparison 851).
Acceptance criteria: The Sample solution is colorless and has no more turbidity than the Standard solution.
• Optical Rotation, Specific Rotation 781S
Sample solution: 100 mg/mL in 2 N hydrochloric acid
Acceptance criteria: +24.8 to +25.3, determined at 20
• pH 791: 6.77.2, in a solution (1 in 20)
• Loss on Drying 731: Dry a sample at 100 for 5 h: it loses NMT 0.5% of its weight.
• Packaging and Storage: Preserve in tight containers.