Analysis of sugar degradation products with α-dicarbonyl structure in carbonated soft drinks by UHPLC-DAD-MS/MS

Sugar-sweetened carbonated soft drinks (CSDs) are broadly consumed worldwide. The added sugar, particularly high-fructose corn syrup (HFCS), can be an important source of sugar degradation products, such as α-dicarbonyl compounds. This study recorded the α-dicarbonyl profile in CSDs by ultrahigh-performance liquid chromatography with hyphenated diode array-tandem mass spectrometry after derivatization with o-phenylenediamine. Thus, 3-deoxy-D-erythro-hexos-2-ulose (3-DG), D-lyxo-hexos-2-ulose (glucosone), 3-deoxy-D-threo-hexos-2-ulose (3-DGal), 1-deoxy-D-erythro-hexos-2,3-diulose (1-DG), 3,4-dideoxyglucosone-3-ene (3,4-DGE), methylglyoxal, and glyoxal were identified as major α-dicarbonyls and, with the exception of glyoxal, quantified (recovery rates, 85.6-103.1%; RSD, 0.8-3.6%). Total α-dicarbonyl concentration in 25 tested commercial products ranged between 0.3 and 116 μg/mL and was significantly higher in HFCS-sweetened CSDs compared to CSDs sweetened with HFCS and sucrose or with sucrose alone. Predominant was 3-DG (≤87 μg/mL) followed by glucosone (≤21 μg/mL), 3-DGal (≤7.7 μg/mL), 1-DG (≤2.8 μg/mL), methylglyoxal (≤0.62 μg/mL), and 3,4-DGE (≤0.45 μg/mL).