A Method for the Measurement of Lutein in Infant Formula

Abstract

Lutein is an antioxidant that is deposited in the macular region of the eye and is crucial to macular function. Lutein is present in human milk and recently has been added to infant and toddler formulas. A method for the extraction and quantification of lutein from lutein-fortified infant formula and toddler milk products was developed. The lipids and carotenoids were extracted from the samples with ethanol and hexane:tetrahydrofuran. Polar xanthophylls were ex-tracted from the organic mixture with ethanol:water, leaving behind lipids and less polar carotenoids. The ethanol:water extracts were dried, reconstituted in mobile phase, and the lutein was quantified by high performance liquid chromatography with UV detection. A C30 carotenoid column and a mobile phase gradient of methyl-tert-butyl ether and methanol were used for the chromatographic separation. Validation data showed repeatability with relative stan-dard deviations < 4% and intermediate precision with relative standard deviations <20% at a low fortification level, 25 mcg lutein/L, and <12% at a high fortification level, 200 mcg lutein/L. Overall recoveries from sample matrix ranged from 88% to 106%. This liquid:liquid extraction method for the quantification of lutein in infant formulas is precise and accurate. Keywords: Lutein; carotenoid; infant formula; toddler milk; xanthophylls.