Origin and yields of acetic acid in pentose-based Maillard reaction systems.
The formation of acetic acid from pentoses was studied in aqueous buffered systems (90-120 degrees C, pH 6.0-8.0) containing equimolar concentrations of 13C-labeled xylose and glycine. Acetic acid was quantified by gas chromatography-mass spectroscopy using an isotope dilution assay. Acetic acid was mainly formed from the C-1/C-2 carbon atoms of xylose (77-87%), while small amounts were also formed from the C-4/C-5 atoms of the pentose sugar (9-15%). Temperature and pH had only a small effect on the relative contribution of the sugar carbon atoms to acetic acid. These results support beta-dicarbonyl cleavage of 1-deoxypento-2,4-diulose as a major pathway leading to acetic acid in pentose-based Maillard reaction systems under food processing conditions. Acetic acid was confirmed as a major degradation product of pentoses at the early stage of the Maillard reaction, yielding 16 mol% and 28 mol% at pH 6.0 and pH 8.0, respectively.
Davidek
Tomas
T
Nestle Product Technology Centre Orbe, Nestec LTD., Orbe, Switzerland. tomas.davidek@rdor.nestle.com
Gouézec
Elisabeth
E
Devaud
Stéphanie
S
Blank
Imre
I
D019342:Acetic Acid / Q000737:chemistry*; D005998:Glycine / Q000737:chemistry; D006868:Hydrolysis; D007700:Kinetics; D015416:Maillard Reaction; D010429:Pentoses / Q000737:chemistry*; D014994:Xylose / Q000737:chemistry
D010429:Pentoses; D014994:Xylose; D019342:Acetic Acid; D005998:Glycine