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E 469 Enzymatically hydrolysed carboxymethyl cellulose, ezymatically hydrolysed cellulose gum - EU specification

COMMISSION REGULATION (EU) No 231/2012 of 9 March 2012


Sodium carboxymethyl cellulose, enzymatically hydrolysed


Enzymatically hydrolysed carboxymethylcellulose is obtained from carboxymethylcellulose by enzymatic digestion with a cellulase

produced by Trichoderma longibrachiatum (formerly T. reesei)


Chemical name: Carboxymethyl cellulose, sodium, partially enzymatically hydrolysed

Chemical formula: Sodium salts of polymers containing substituted anhydroglucose units with the general formula:

[C 6 H 7 O 2 (OH) x (OCH 2 COONa) y ] n where n is the degree of polymerisation

x = 1,50 to 2,80

y = 0,2 to 1,50

x + y = 3,0

(y = degree of substitution)

Molecular weight: 178,14 where y = 0,20. 282,18 where y = 1,50. Macromolecules: Not less than 800 (n about 4)

Assay: Not less than 99,5 %, including mono- and disaccharides, on the dried


White or slightly yellowish or greyish, odourless, slightly hygroscopic granular or fibrous powder


Solubility: Soluble in water, insoluble in ethanol

Foam test: Vigorously shake a 0,1 % solution of the sample. No layer of foam appears. This test distinguishes sodium carboxymethyl cellulose, whether hydrolysed or not, from other cellulose ethers and from alginates and natural gums

Precipitate formation: To 5 ml of a 0,5 % solution of the sample add 5 ml of a 5 % solution of copper or aluminium sulphate. A precipitate appears. This test distinguishes sodium carboxymethyl cellulose, whether hydrolysed or not, from other cellulose ethers and from gelatine, carob bean gum and tragacanth gum

Colour reaction: Add 0,5 g of the powdered sample to 50 ml of water, while stirring to produce a uniform dispersion. Continue the stirring until a clear solution is produced. Dilute 1 ml of the solution with 1 ml of water in a small test tube. Add 5 drops of 1-naphthol TS. Incline the tube, and carefully introduce down the side of the tube 2 ml of sulphuric acid so that it forms a lower layer. A red-purple colour develops at the interface

Viscosity (60 % solids): Not less than 2 500 kgm – 1 s – 1 at 25 °C corresponding to an average molecule weight of 5 000 Da

pH: Not less than 6,0 and not more than 8,5 (1 % colloidal solution)


Loss on drying: Not more than 12 % (105 °C to constant weight)

Degree of substitution: Not less than 0,2 and not more than 1,5 carboxymethyl groups per anhydroglucose unit on the dried basis

Sodium chloride and sodium glycolate: Not more than 0,5 % singly or in combination

Residual enzyme activity: Passes test. No change in viscosity of test solution occurs, which indicates hydrolysis of the sodium carboxymethyl cellulose

Lead: Not more than 3 mg/kg