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Synonyms: Polysaccharide gum produced by the fermentation of carbohydrate with the bacterium Xanthomonas campestris
CAS Number: *********2, Molecular Weight: polymer, Chemical Formula: (C*5H*9O*9)n, EINECS EC Number: ********2, FEMA: ***-,

Xanthan Gum BP Grade
Ph Eur
Action and use: Excipient.

DEFINITION
High-molecular-mass anionic polysaccharide produced by fermentation of carbohydrates with Xanthomonas campestris.
Xanthan gum has a relative molecular mass of approximately 1 — **6. It exists as the sodium, potassium or calcium salt.
Content: Minimum 1.5 per cent of pyruvoyl groups (C3H3O2; Mr *1.1) (dried substance).

CHARACTERS
Appearance: White or yellowish-white, free-flowing powder.
Solubility: Soluble in water giving a highly viscous solution, practically insoluble in organic solvents.
IDENTIFICATION
A. In a flask, suspend 1 g in *5 ml of 0.1 M hydrochloric acid . Close the flask with a fermentation bulb containing barium hydroxide solution and heat carefully for 5 min. The barium hydroxide solution shows a white turbidity.
B. To **0 ml of water, previously heated to *0 °C and stirred rapidly with a mechanical stirrer in a **0 ml beaker, add, at the point of maximum agitation, a dry blend of 1.5 g of carob bean gum and 1.5 g of the substance to be examined. Stir until the mixture forms a solution, and then continue stirring for *0 min or longer. Do not allow the water temperature to drop below *0 °C during stirring. Discontinue stirring and allow the mixture to stand for at least 2 h. A firm rubbery gel forms after the temperature drops below *0 °C but no such gel forms in a 1 per cent control solution of the sample prepared in the same manner but omitting the carob bean gum.

TESTS
pH: 6.0 to 8.0 for a *0.0 g/l solution.
Viscosity: Minimum **0 mPa·s.
*-Propanol: To pass Gas chromatography test. Limit *-propanol: maximum **0 ppm.
Other polysaccharides: To pass Thin-layer chromatography test.
Loss on drying: Maximum *5.0 per cent, determined on 1.**0 g by drying in an oven at **5 °C for 2.5 h.
Total ash: 6.5 per cent to *6.0 per cent.
Microbial contamination: Total viable aerobic count not more than **3 bacteria and **2 fungi per gram, determined by plate count. It complies with the test for Escherichia coli.

Xanthan Gum USP NF Grade
Xanthan Gum is a high molecular weight polysaccharide gum produced by a pure-culture fermentation of a carbohydrate with Xanthomonas campestris, then purified by recovery with Isopropyl Alcohol, dried, and milled. It contains Dglucose and D-mannose as the dominant hexose units, along with D-glucuronic acid, and is prepared as the sodium, potassium, or calcium salt. It yields not less than 4.2 percent and not more than 5.0 percent of carbon dioxide, calculated on the dried basis, corresponding to not less than *1.0 percent and not more than **8.0 percent of Xanthan Gum.

Identification: To **0 mL of water in a ***-mL beaker, previously heated to *0 and stirred rapidly by mechanical means, add, at the point of maximum agitation, a dry blend of 1.5 g of Xanthan Gum and 1.5 g of locust bean gum. Stir until the mixture dissolves, and then continue stirring for *0 minutes longer. Do not allow the temperature of the mixture to drop below *0 during the stirring. Discontinue stirring, and allow the mixture to cool at room temperature for not less than 2 hours: a firm, rubbery gel forms after the temperature drops below *0 , but no such gel forms in a control solution prepared in the same manner with 3.0 g of Xanthan Gum and without locust bean gum.
Viscosity: Place **0 mL of water in a ***-mL beaker, and add a dry blend of 3.0 g of Xanthan Gum and 3.0 g of potassium chloride slowly while stirring at **0 rpm, using a low-pitched propeller-type stirrer. Add an additional quantity of *4 mL of water, rinsing the walls of the beaker. Approximately *0 minutes after the addition of the dry blend of Xanthan Gum and the potassium chloride to the water, remove the beaker from the propeller-type stirrer, and vigorously stir the solution by hand to ensure that all the particles around the edge of the beaker are in solution. Return the beaker to the stirrer, and agitate at **0 rpm for a total mixing time of 2 hours. Then adjust the temperature to *4 ± 1 , and stir by hand in a vertical motion to eliminate any thixotropic effects or layering.
[NOTE: Each hand mixing should be not more than *5 to *0 seconds, and the last hand mixing should occur immediately prior to measuring the viscosity.] Equip a suitable rotational viscosimeter with a spindle having a cylinder 1.*7 cm in diameter and 0.*6 cm high attached to a shaft 0.*2 cm in diameter, the distance from the top of the cylinder to the lower tip of the shaft being 2.*4 cm, and the immersion depth being 5.*0 cm (No. 3 spindle). With the spindle rotating at *0 rpm, immediately observe and record the scale reading. Convert the scale readings to centipoise by multiplying the readings by the constant for the viscosimeter spindle and speed employed. The viscosity at *4 is not less than **0 centipoise.
Microbial limits: It meets the requirements of the tests for Salmonella species and Escherichia coli.
Loss on drying: Dry it at **5 for 2.5 hours: it loses not more than *5.0% of its weight.
Ash: Accurately weigh about 3 g in a tared crucible, and incinerate at about **0 until free from carbon. Cool the crucible and its contents in a desiccator, and weigh: the weight of the ash is between 6.5% and *6.0%, calculated on the dried basis.
Arsenic: 3 ug per g.
Lead: the limit is *@********************y metals: The limit is 0.**3%.
Limit of isopropyl alcohol: To pass the test, not more than 0.**5% is found.
Pyruvic acid: To pass the test.

Xanthan Gum FCC Food Grade
INS: **5 CAS: [*********2]

DESCRIPTION
Xanthan Gum occurs as a cream colored powder. It is a high-molecular-weight polysaccharide gum produced by a pureculture fermentation of a carbohydrate with Xanthomonas campestris, purified by recovery with isopropyl alcohol, dried, and milled. It contains D-glucose and D-mannose as the dominant
hexose units, along with D-glucuronic acid and pyruvic acid, and it is prepared as the sodium, potassium, or calcium salt. It is readily soluble in hot or cold water, but it is insoluble in alcohol. Its solutions are neutral.
Function: Stabilizer; thickener; emulsifier; suspending agent; bodying agent; foam enhancer.

REQUIREMENTS
Identification: Transfer **0 mL of water, previously heated to *0°, into a ***-mL beaker and stir rapidly with a mechanical stirrer. At the point of maximum agitation, add a dry blend of 1.5 g of sample and 1.5 g of locust bean gum. Stir until the mixture goes into solution, and then continue stirring for *0 min longer. Do not allow the water temperature to drop below *0°. Discontinue stirring, and allow the mixture to cool at room temperature for at least 2 h. A firm, rubbery gel forms after the temperature of the mixture drops below *0°. No such gel forms in a 1% control solution of sample prepared in the same manner but omitting the locust bean gum.
Assay: A sample yields, on the dried basis, not less than 4.2% and not more than 5.4% of carbon dioxide (CO2), corresponding to between *1.0% and **7.0% of Xanthan Gum.
Isopropyl Alcohol: Not more than 0.**5%.
Lead: Not more than 2 mg/kg.
Loss on Drying: Not more than *5.0%.
Pyruvic Acid: Not less than 1.5%.
Viscosity: Passes test.