Determination of vitamin a in fortified milk powders using high performance liquid chromatography
Woollard, D.C.; Woollard, G.A.
New Zealand Journal of Dairy Science and Technology 16(2): 99-112
ISSN/ISBN: 0300-1342 Accession: 005129242
A fast and reliable method was developed to extract vitamin A from milk powder without the use of saponification. The milk powder is first dispersed in a non-aqueous solvent mixture to release the natural and added vitamin A esters. The lipid fraction is then partitioned into hexane, a portion of which is injected directly into a high performance liquid chromatograph without further concentration or purification. The chromatograph conditions comprise a normal phase silica column with an isocratic hexane: chloroform mobile phase. This system can adequately tolerate the injection of large quantities of lipid material and simultaneously permit separation of vitamin A from the fat.