Paper Chromatography and Paper Electrophoresis of Food Preservatives

A new solvent system was given for the chromatography of food preservatives; benzoic acid, salicylic acid, p-hydroxybenzoic acid and it's esters, p-chlorobenzoic acid, sorbic acid, resorcinol and β-naphtol with the ascending method on Toyo Roshi No. 50 paper at 20-25°. Cyclohexanol-ammonium carbonate buffer gave results in 30 hours. Spots were detected by absorption when the paper was examined in ultraviolet light and with color reagcnts of the methyl red or diazo spray reagent. Rf values for this solvent were listed for these substances. Each substance was separated except in the case of mixture of benzoic acid and sorbic acid. However in this case, these two substances were identified by measuring spectrophotometrically the alcohol solution extracted from the part containing the substances on paper chromatogram.Horizontal paper electrophoresis on Toyo Roshi No. 51 paper for 1.5-2 hours at 20V per cm with buffer consisted of dimethylformamide, pyridine, acetic acid and water (pH 5.6) or of butanol, ammonia, acetic acid and water (pH 5.0) was useful. MNC (the ratio of the migration of the substances of New Coccine) and colors given with the methyl red, FeCl3 and diazo spray reagents were tabulated adding dehydroacetic acid to above substances. Data was also given for citric acid and tartaric acid.Sake (Japanese wine), soy etc., was acidified with HCl, extracted with ether, purified as ammonium-salts and submitted to paper chromatography and paper electrophoresis with similar technique.