Differentiation of qualified tea beverages from spoiled ones by the LC-MS–based analysis of their polycarboxylic acids

Abstract Polycarboxylic acids (PACs) are important metabolic products in almost all living bodies, yet current analytical methods for detection of PACs tea beverages still unsatisfactory due to the complex matrix and physicochemical properties PACs. In this work, a rapid method was developed simultaneous determination 7 PACs, including tartaric acid, α-ketoglutaric malic malonic cis-aconitic succinic fumaric beverages, based on selective removal combination with liquid chromatography–mass spectrometry (LC-MS) analysis. By stirring activated carbon Na2CO3 solution, selectively removed, were retained supernatant diluted solution. Under optimized parameters, limit quantitation range 1–50 ng/mL, content 8 determined recovery 72.2%–122.5%. The contents acid found be greater than those non-tea beverages. Moreover, concentration these multiplied many times their deterioration period, especially acid. These results indicated that can selected as criterion differentiate qualified from spoiled