Qualitative and Quantitative Profiling of Fructose\nDegradation Products Revealed the Formation of Thirteen Reactive Carbonyl\nCompounds and Higher Reactivity Compared to Glucose

Fructose occurs in\nfoods and as a metabolite in vivo. It can be\ndegraded, leading to the formation of reactive carbonyl compounds,\nwhich may influence food properties and have an impact on health.\nThe present study performed an in-depth qualitative and quantitative\nprofiling of fructose degradation products. Thus, the α-dicarbonyl\ncompounds 3-deoxyglucosone, glucosone, methylglyoxal, glyoxal, hydroxypyruvaldehyde,\nthreosone, 3-deoxythreosone, and 1-desoxypentosone and the monocarbonyl\ncompounds formaldehyde, acetaldehyde, glycolaldehyde, glyceraldehyde,\nand dihydroxyacetone were detected in fructose solutions incubated\nat 37 °C. Quantitative profiling after 7 days revealed 4.6–271.6-fold\nhigher yields of all degradation products from fructose compared to\nglucose. Except for 3-deoxyglucosone, the product formation appeared\nto be metal dependent, indicating oxidative pathways. CaCl<sub>2</sub> and MgCl<sub>2</sub> partially reduced fructose degradation. Due\nto its high reactivity compared to glucose, particularly toward metal-catalyzed\npathways, fructose may be a strong contributor to sugar degradation\nand Maillard reaction in foods and in vivo.