Identification and determination of 3-deoxyglucosone and glucosone in carbohydrate-rich foods.

BACKGROUND: α-Dicarbonyl compounds (α-DCs) such as 3-deoxyglucosone (3-DG) and glucosone are markers of both Maillard and degradation reactions of sugars and also of certain enzymatic processes. However, quantitation of these compounds is not straightforward when more abundant carbohydrates are present in real samples. Therefore in this work a GC/MS method was developed to separate monosaccharides, 3-DG and glucosone and applied to analyze them in carbohydrate-rich food products. Difructose anhydrides (DFAs), known markers of sugar degradation, were also determined. The effect of time and temperature in the production and storage of these compounds was also evaluated. RESULTS: Under optimized conditions, good separation between monosaccharides and α-DCs was achieved. Must syrups showed the highest concentrations of 3-DG and glucosone (average values 9.2 and 5.8 mg g(-1) respectively). Coffee substitutes based on carob, chicory and blends showed the highest content of DFAs. Heating and storage assays proved that production of 3-DG was influenced by temperature, while glucosone was more affected by storage time. CONCLUSION: The proposed method allows the rapid quantitation of 3-DG and glucosone along with carbohydrates and DFAs in different food products, which is essential to determine their degradation level. Moreover, the α-DC content in several foods is reported for the first time.