Baby foods are exposed to elevated temperatures during processing treatments such as sterilization or spray drying. These treatments decompose sugars leading to the formation of a-dicarbonyl compounds that are of importance since they have been associated with several metabolic disorders. In this study, an analytical method based on high-performance liquid chromatography coupled with electrospray ionization mass spectrometry (HPLC-ESI-MS) was used to determine a-dicarbonyl compounds in baby foods. The method entailed aqueous extraction of a-dicarbonyl compounds from the samples and derivatization with o-phenylenediamine prior to chromatographic analysis. The results indicated that major degradation product was 3-deoxyglucosone in the samples including cereal-based infant formula, canned fruit and vegetable puree. Its concentration ranged between 3.9 and 827.1 mg/kg in infant formula and between 26.7 and 92.3 mg/kg in fruit puree samples. The concentrations of glucosone, 1-deoxyglucosone, 5-hydroxymethy1-2-furfural, furfural, glyoxal, methylglyoxal, and dimethylglyoxal levels were rather low.