Subsidiary color

Higher sulfonated subsidiary colors (as sodium salts)—not more than 1.0%... 

During the synthesis of food dyes, as with any chemical reaction, the product that is formed contains impurities, since the reactants themselves are usually impure and side reactions can also occur. The impurities can be of three types Uncombined intermediates are compounds from which a color is directly synthesized and do not impart color to the product subsidiary colors are colored compounds that are structurally related to the product other impurities include substances that may arise from contamination of the intermediates or other reagents used during synthesis... 

Yamada et al. (201) developed a method for the determination of starting materials (7-hydroxy-1,3,6-naphthalenesulfonic acid, G-salt, R-salt, Schaeffer s salt, and naphthionic salt) and subsidiary colors (Ponceau 6R, amaranth, and fast red) in Ponceau 4R. It consisted of an ODS column and gradient elution of acetonitrile in 0.02 M ammonium acetate. 

Lower-sulfonated subsidiary colors of sunset yellow, among them 5-(phenylazo)-6-hydroxy-naphthalene-2-sulfonic acid (ANSC) and 4-[(2-hydroxynaphthalene-l-yl)azo]benzenesulfonic acid (BNSC), were determined by reverse-phase HPLC using Novapak Cl 8 and gradient elution with a water-tetrahydrofuran solvent system buffered with ammonium acetate (192). 

Indigotine was separated from isatin-5-sulfonic acid (decomposition product), 5,7 -disulfoindigo (isomeric subsidiary color) and 5-sulfoindigo (lower sulfonated subsidiary color) by reverse-phase HPLC on Altex Ultraspher ODS using gradient elution (215). 

JE Bailey. Determination of the lower sulfonated subsidiary colors in FD C yellow no. 6 by reversed-phase high performance liquid chromatography. J Chromatogr 347 163-172, 1985. 

RJ Calvey, AL Goldberg. High performance liquid chromatographic determination of subsidiary colors in FD C red no. 3. J Assoc Off Anal Chem 65(5) 1080-1085, 1982. 

M Yamada, Y Kato, M Nakamura, S Ishimitsu, T Shibata, Y Ito. Determination and survey of starting materials and subsidiary colors in new coccine by high performance liquid chromatography. J Food Hyg Soc Jpn 36(3) 417-422, 1995. 

JE Bailey. High pressure liquid chromatographic determination of intermediates and subsidiary colors in FD C blue no. 2. J Assoc Off Anal Chem 63(3) 565-571, 1980. 

Higher and Lower Sulfonated Subsidiary Colors (as sodium salts) Not more than 1.0% each. 

Standard Solution Transfer approximately 1 g of purified Allura Red (free of subsidiary colors), accurately weighed, into a 50-mL volumetric flask. Add 50 mg each of lower and higher sulfonated subsidiary colors, accurately weighed, dissolve in and dilute to volume with water. Store in the dark. 

Subsidiary Colors Not more than 6.0%, combined, of isomeric disodium salts of ethyl[4-[/t-[ethyl(p-sulfobenzyl) amino] -I- (o-sulfophenyl) benzylidene]-2,5-cyclohexadien-1-ylidene](p-sulfobenzyl) ammonium hydroxide inner salt, and ethyl [ 4- [p- [ ethyl (o-sulfobenzyl) amino ] -a- (o- sulfophenyl) benzylidene ] -2,5-cyclohexadien- 1-ylidene ] (o-sulfobenzyl) ammonium hydroxide inner salt. 

When the plate has dried, scrape off all the colored bands above the Brilliant Blue, which remains close to the origin, into a 30-mL beaker. Extract the subsidiary colors with three 6-mL portions of 95% ethanol, or until no color remains on the gel by visual inspection. Record the volume of ethanol used and the spectrum of the solution between 400 and 700 nm. Calculate the percent of subsidiary colors by the formula... 

Scrape off each subsidiary color and extract with 3- to 5-mL portions of 50% aqueous ethanol until no color remains on the gel by visual inspection. Dilute each sample to 13 to 15 mL, add a few drops of ammonium hydroxide, and record the final volume. Repeat this procedure for the band of Erythrosine using 10- to 20-mL portions of 50% ethanol, and dilute the eluant to 250 mL in a volumetric flask after adding enough... 

Record the spectrum of each solution between 400 and 600 nm, and calculate the quantity, in percent (P), of each subsidiary color by the equation... 

Subsidiary Colors Not more than 6.0%, total, of isomeric inner salt disodium salt of N-ethyl-N-[4-[[4-[ethyl[(3-sulfo-phenyl)methyl] amino]phenyl] (4-hydroxy-2-sulfophenyl)-methylene] - 2,5- cyclohexadien-1 -ylidene] -4- sulfobenzene-methanaminium hydroxide, Ar-ethyl-lV-[4-[[4-[ethyl[(4-sulfo-phenyl) methyl ] amino ] phenyl ] (4-hydroxy-2-sulfophenyl)-methylene]-2,5-cyclohexadien-l-ylidene]-4-sulfobenzene-methanaminium hydroxide, and /V-ethyl-/V-[4-[[4-[ethyl[(2-sulfophenyl) methyl] amino]phenyl] (4-hydroxy-2-sulfophe-nyl) methylene ] - 2,5-cyclohexadiene-1 -ylidene ] - 3- sulfoben-zenemethanaminium hydroxide. 

Loss on Drying (Volatile Matter) at 135°, Chlorides and Sulfates (as sodium salts) Determine as directed in Loss on Drying (Volatile Matter) under Colors, Appendix IIIC. Subsidiary Colors... 

Subsidiary coloring matters carotenoids other than beta-carotene, <3.0% of total coloring matters. 

Subsidiary coloring matters excluding provision above,... 

Ether-extractable matter <0.2% under neutral conditions Assay 85% total coloring matters as the sodium salt Subsidiary colors <5%... 

Sunset fellow FCF (Food Yellow No 5), six subsidiary colors, and four raw materials/intermediates were separated on a 40°C C,g column (2 = 232nm) using a 20-min 100/0 —> 65/35 water (0.04% ammonium carbonate)/acetonitrile gradient... 

Quinoline Yellow is a quinophthalone dye consisting essentially of a mixture of monosulfonates, disulfonates (principal component), and trisulfonates, and subsidiary coloring... 

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