abstract
Non-enzymatic transglycosylation reactions are known to occur under high sugar concentrations, high temperatures, low moisture environments and acidic conditions. Although honey is not a thermally processed food, its high sugars concentration under an acidic and low moisture environment for prolonged periods of time may also promote these reactions. To test this hypothesis six model solutions containing combinations of sucrose and glucose or fructose, prepared with water and diluted citric acid at pH 4.0 and 2.0, were incubated at 35 degrees C during up to 5 months, similar to the honey under hive conditions. Electrospray ionization mass spectrometry (ESI-MS) allowed to observe polymerization products soon after their incubation. After 5 months, a degree of polymerization of 6 was detected, similarly to the honey samples used for comparison. Maltose, isomaltose, inulobiose, sophorose, gentiobiose, 1-kestose and panose were detected in both model solutions and honey samples, showing that non-enzymatic transglycosylation reactions also contribute to oligosaccharides origin and diversity in honey.
keywords
IDENTIFICATION; TRISACCHARIDES; ACIDITY; STORAGE; SUGARS
subject category
Chemistry
authors
Silva, SR; Moreira, ASP; Domingues, MDM; Evtuguin, DV; Coelho, E; Coimbra, MA
our authors
Ana Sofia Pereira Moreira
Junior Researcher
Dmitry Evtyugin
Associate Professor with Aggregation
Elisabete Verde Martins Coelho
Post-Doc Fellowshipacknowledgements
Authors thank to FCT/MEC financial support for QOPNA (FCT UID/QUI/00062/2019), CESAM (UID/AMB/50017/2019), European Regional Development Fund, RNEM (LISBOA-52201-0145-FEDER-402-022125), through national funds, and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020. Elisabete Coelho thanks FCT for the postdoctoral grant SFRH/BPD/70589/2010 and the research contract funded by national funds (OE), through FCT, in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. Soraia P. Silva also thanks FCT for the doctoral grant SFRH/BD/136471/2018.