Cochineal Extract ( FAO )


Prepared at the 55th JECFA (2000), published in FNP 52 Add 8 (2000) superseding specifications prepared at the 51st JECFA (1998), published in st FNP 52 Add 6 (1998). No ADI allocated at the 21 JECFA in 1977. SYNONYMS CI Natural Red 4, CI (1975) No. 75470; INS No. 120 DEFINITION Cochineal consists of the dried bodies of the female insect Dactylopius coccus Costa; Cochineal extract is the concentrated solution obtained after removing the alcohol (ethanol and/or methanol) from an aqueous, aqueous alcoholic or alcoholic extract of cochineal; the colouring principle is chiefly carminic acid; commercial products may also contain proteinaceous material derived from the source insect. In commercial products the colouring principle may also be present in association with ammonium, potassium or sodium cations, singly or in combination, and these cations may also be present in excess. Chemical names 7-beta-D-glucopyranosyl-3,5,6,8-tetrahydroxy-1-methyl-9,10-dioxoanthracene- 2-carboxylic acid C.A.S. number 1343-78-8 (cochineal) 1260-17-9 (carminic acid) Chemical formula C22 H20O13 (Carminic acid) Structural formula Carminic acid: Formula weight Carminic acid: 492.39 Assay Not less than 2.0% C22 H20O13 DESCRIPTION Dark red liquid Colour FUNCTIONAL USES CHARACTERISTICS IDENTIFICATION

Solubility (Vol. 4) Freely soluble in water Colour reactions Make a solution of the sample slightly alkaline by adding 1 drop of 10% sodium hydroxide or potassium hydroxide solution. A violet colour is produced. Add a small sodium dithionite (Na S O ) crystal to acid, neutral or alkaline 2 2 4 solutions of the sample. The solutions are not decolourized. Dry a small quantity of the sample in a porcelain dish. Cool thoroughly and treat the dry residue with 1 or 2 drops of cold sulfuric acid TS. No colour change occurs. Acidify a dispersion of the sample in water with 1/3 volume of hydrochloric acid TS and shake it with amyl alcohol. Wash the amyl alcohol solution 2-4 times with an equal volume of water to remove hydrochloric acid. Dilute the amyl alcohol solution with 1-2 volumes of petroleum ether (40-60o) and shake with a few small portions of water to remove colour. Add, dropwise, 5% uranium acetate, shaking thoroughly after each addition. A characteristic emerald- green colour is produced. PURITY Protein (Vol. 4) Not more than 2.2% Proceed as directed under Nitrogen Determination (non-ammonia N x 6.25) Ethanol (Vol. 4) Not more than 150 mg/kg Proceed as directed under Residual solvent Methanol (Vol.4) Not more than 150 mg/kg Proceed as directed under Residual solvent Microbiological criteria Salmonella: Negative per test (Vol. 4) Lead (Vol. 4) Not more than 2 mg/kg Determine using an atomic absorption technique appropriate to the specified level. The selection of sample size and method of sample preparation may be based on the principles of the method described in Volume 4, “Instrumental Methods.” METHOD OF Weigh accurately about 1 g of the sample, dissolve in 30 ml of boiling 2N ASSAY hydrochloric acid, and cool. Transfer quantitatively to a 1000 ml volumetric flask, dilute to volume with water, and mix. Determine the absorbance of the solution in a 1 cm cell at the wavelength of maximum absorbance (about 494 nm) using water as the blank. Calculate the percentage of carminic acid in the sample using the formula: where A = absorbance of the sample solution; W = weight, in mg, of the sample taken; and 1.39 = absorbance of a solution of carminic acid having a concentration of 100 mg per 1000 ml If the measured absorbance is not within the range 0.650 to 0.750, prepare another sample and adjust the weight accordingly.

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