Abstract
The method for the qualitative analysis of polysorbate in foods was studied. Polysorbate in foods was extracted with a mixture of dichloromethane and ethanol, and the extracts were applied to thin-layer chromatography (TLC) using silica gel plate.
Comparison of the recovery of polysorbate added in soft drink was carried out with 8 kind of extraction solvents, the highest recovery was obtained by the use of the dichloromethane·ethanol (1: 1v/v) mixture. Polysorbate was identified by thin-layer chromatography using chloroform, methanol, acetic acid and water and n-propanol, chloroform·methanoland 28% ammonia water as the solvents for thin-layer chromatography, since there were some color positive substances to cobalt thiocyanate reagent in food extracts.
This method was applied to eighteen kinds of food, for example, bread, cake mix, pudding etc, but no blue spot was found corresponding to polysorbate 80 except canned pudding, into which polysorbate 80 was used. The method, however, could net discriminate polysorbate and polyoxyethylene higher alcohol as were the case in the analytical methods by FDA or Hall et al.
