Determination of organic acids in sugar cane process juice by high-performance liquid chromatography: improved resolution using dual Aminex HPX-87H cation-exchange columns equilibrated to different temperatures
Blake, J.D.; Clarke, M.L.; Richards, G.N.
Journal of Chromatography 398: 265-277
1987
ISSN/ISBN: 0021-9673 PMID: 3654841 Document Number: 297901
The application of high-performance liquid chromatography to the quantitative analysis of organic acids in sugar cane process juice is described. Separation of these acids is achieved on Aminex HPX-87H cation-exchange columns. Resolution is improved by connecting two columns in series and equilibrating them at different temperatures. The acids in the sample are first isolated on DEAE-Sephadex A-25 anion-exchange resin equilibrated with 0.5 M isobutyric acid. They are then eluted with 0.5 M sulphuric acid and injected directly onto the HPLC column after filtration through a 0.45-.mu.m membrane. This method allows the simultaneous determination of oxalic, cis-aconitic, citric, phosphoric, malic, trans-aconitic, succinic, glycolic, lactic, formic and acetic acids. Isobutyric acid is also separated on this system and provides a useful guide to the loading capacity of the anion-exchange resin.