Application of gel permeation chromatography and nonaqueous reverse phase chromatography to high pressure liquid chromatographic determination of retinyl palmitate and beta-carotene in oil and margarine.
A high pressure liquid chromatographic method was developed using high pressure gel permeation chromatography (HP-GPC) and high pressure reverse phase chromatography (RP-HPLC) for quantitation of retinyl palmitate and beta-carotene. HP-GPC was used for fractionation of vitamin A active compounds from oil preliminary to quantitation on nonaqueous RP-HPLC. HP-GPC fractionation was completed on oil and margarine dissolved in methylene chloride by 2 elution passes through 2 muStyragel (100 angstrom) columns connected in series with methylene chloride as the mobile phase. RP-HPLC separation of retinyl palmitate and beta-carotene was achieved on muBondapak C18 (10 micrometers), using methylene chloride-acetonitrile (30+70). Based on 10 repetitive analyses, recoveries of added beta-carotene and retinyl palmitate from vegetable oils were 98.6+/-2.9 and 95.2+/-2.6%, respectively. The coefficients of variation were 2.9% for beta-carotene and 2.7% for retinyl palmitate. The determination of vitamin A activity in 7 margarine brands with label claims of 10% U.S.RDA/serving revealed that all but one of the margarines contained at least 94% of the label claim. Vitamin A activity in the margarines ranged from 90.6 to 110.8% of the label declaration.
D002338:Carotenoids / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004224:Diterpenes; D008383:Margarine / Q000032:analysis*; D009821:Oils / Q000032:analysis*; D010168:Palmitates / Q000032:analysis; D000084562:Retinyl Esters; D014801:Vitamin A / Q000031:analogs & derivatives* / Q000032:analysis
D004224:Diterpenes; D009821:Oils; D010168:Palmitates; D000084562:Retinyl Esters; D014801:Vitamin A; C014794:retinol palmitate; D002338:Carotenoids; D008383:Margarine