Determination of sorbic acid in margarine and butter by high-performance liquid chromatography with fluorescence detection.
A procedure is reported for the separation and determination of sorbic acid, as a derivative of 4-bromoethyl-6,7-dimethoxycoumarin, by reversed-phase high-performance liquid chromatography with fluorescence detection using enanthic acid as an internal standard. Sorbic acid, separated from samples of commercial margarine and butter by steam distillation, was evaluated using the proposed procedure and by UV absorption and visible spectrophotometric methods (AOAC). The preparation of the calibration graph and the determination of sorbic acid with the visible spectrophotometric method was improved. The sorbic acid content determined using UV and visible spectrophotometric methods was higher than that obtained with the reversed-phase performance liquid chromatographic method owing to the presence of interfering substances in the samples. The range of recovery and the precision of the proposed method and the reference methods are also reported.
Burini
G
G
Istituto di Chimica Bromatologica, Facolta di Farmacia, Universita degli Studi di Perugia, Italy.
Damiani
P
P
D000818:Animals; D002079:Butter / Q000032:analysis*; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D043844:Crown Ethers; D004988:Ethers, Cyclic; D007202:Indicators and Reagents; D008383:Margarine / Q000032:analysis*; D012015:Reference Standards; D012996:Solutions; D013011:Sorbic Acid / Q000032:analysis*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
D043844:Crown Ethers; D004988:Ethers, Cyclic; D007202:Indicators and Reagents; D012996:Solutions; C015762:18-crown-6; D002079:Butter; D008383:Margarine; D013011:Sorbic Acid