Characterization of model melanoidins by the thermal degradation profile.
Different types of model melanoidins were thermally degraded, with subsequent identification of the volatiles produced, to obtain and compare the thermal degradation profile of various melanoidins. At first, the volatiles produced from heated glucose/glycine standard melanoidins were compared with glucose/glutamic acid and L-(+)-ascorbic acid/glycine standard melanoidins. In the headspace of heated glucose/glycine melanoidins, mainly furans, were detected, accompanied by carbonyl compounds, pyrroles, pyrazines, pyridines, and some oxazoles. Heating of L-(+)-ascorbic acid/glycine melanoidins resulted in relatively more N-heterocycles, while from glucose/glutamic acid melanoidins no N-heterocycles were formed. In a second part, a chemical treatment was applied to glucose/glycine melanoidins prior to the thermal degradation. Acid hydrolysis was performed to cleave glycosidically linked sugar moieties from the melanoidin skeleton. Nonsoluble glucose/glycine melanoidins were also subjected to an oxidation. The results indicate that the thermal degradation profile is a useful tool in the characterization of different types of melanoidins.
Adams
An
A
Department of Organic Chemistry, Faculty of Agricultural and Applied Biological Sciences, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
Abbaspour Tehrani
Kourosch
K
Kersiene
Milda
M
Venskutonis
Rimantas
R
De Kimpe
Norbert
N
D001205:Ascorbic Acid / Q000737:chemistry; D002849:Chromatography, Gas; D005663:Furans / Q000032:analysis / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry; D005947:Glucose / Q000737:chemistry; D005998:Glycine / Q000737:chemistry; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D015416:Maillard Reaction; D010084:Oxidation-Reduction; D011108:Polymers / Q000737:chemistry*; D013649:Taste; D014835:Volatilization
D005663:Furans; D011108:Polymers; C011908:melanoidin polymers; D005947:Glucose; D001205:Ascorbic Acid; D005998:Glycine