Determination of 10 Organic Acids in Alcoholic Products by Ion Chromatography-Tandem Mass Spectrometry

A method was developed for the determination of 10 organic acids in liquor, yellow rice wine, and dry red wine by ion chromatography-triple quadrupole mass spectrometry (ICMS/MS). First, the liquor samples were diluted with deionized water, degassed with nitrogen, and analyzed by IC-MS/MS. Then, the yellow rice wine and dry red wine samples were purified with different solid-phase extraction cartridges. Finally, the GCB solid -phase extraction cartridge was selected for purification, diluted with deionized water, and analyzed by IC-MS/MS. The samples were separated using a Dionex IonPac AS11-HC anion analysis column with high capacity and strong hydrophilicity, with an KOH aqueous solution as the eluent, which was produced by an automatic generator for gradient elution. After being suppressed using a suppressor, the eluent was injected directly into the electrospray ionization tandem mass spectrometry (ESI-MS/MS), ionized in negative ion mode, detected in multiple reaction monitoring (MRM) mode, and quantified using an external standard method. Oxalic acid, fumaric acid, maleic acid, malic acid, tartaric acid, citric acid, quinic acid, and aconitic acid showed good linear relationships in the range of 0. 05-2 mg/L. Succinic acid and lactic acid showed good linearities in the range of 0. 05-5 mg/L and 0. 05 -10 mg/L, respectively. The correlation coefficients (r(2)) were >0. 99. The limits of detection ( LODs) and limits of quantification (LOQs) were 1. 0 - 8. 0 mu g/L and 3. 5 - 26. 5 mu g/L, respectively. The average recoveries ranged from 83. 0% to 112. 1%, and the relative standard deviations ( RSDs) were <9. 1% in spiked samples at three levels. The proposed method allowed easy pretreatment without using organic solvents or derivatization processing. Overall, the proposed method is accurate, rapid, sensitive, and it is suitable for the qualitative and quantitative analyses of the 10 organic acids in three wine samples. Moreover, it can be used for the determination of flavor and quality of alcoholic products.