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The role of redox reactions in the formation of aroma volatiles, colour and other non-volatiles in the Maillard Reaction was investigated. The electrochemical properties of individual reactants and Maillard model mixtures were monitored via ORP (oxidation-reduction potential) and oxygen electrodes. All models exhibited unique electrochemical activities represented by their corresponding ORP profiles. Investigation into the redox potentials of several model systems demonstrated that the increased negative value of a redox potential is not necessarily correlated with its browning potential. An optimal redox potential range, where browning is favoured, was found to represent a balance between carbonyl and hydroxyl moieties in the structure. Adjustment of this redox potential by introducing reducing or oxidizing species can shift this balance resulting in modifications in browning capacities. However, it was concluded that there is a clear relationship between browning ability and reducing capacity of the model systems. Furthermore, a novel oxidative pyrolysis technique was developed to study the role of oxidative environment on the product distribution during pyrolysis and to investigate the mechanism of formation of non-volatiles through 13C and 15N-label incorporation. Application of this technique to glucoselglycine model system have indicated that most non-volatile Maillard reaction products can arise from glucose oxidation intermediates such as glucosone, gluconic acid and deoxyglucosones. To study the specific role of redox reactions in the formation of non-volatiles, a post-pyrolytic derivatization technique was developed and optimized. Several non-volatile end products were identified and mechanistically confirmed to involve oxidation and reduction reactions for their formation, such as lactones, hydroxylated benzenes and hydroxylated pyrazine. The latter was identified and confirmed to be generated via the dimerization of glycine and subsequent oxidation. In addition, the formation of different volatiles such as pyrazole, imidazole and oxazole was mechanistically confirmed to depend on redox reactions.

Thesis (M.Sc.). / Written for the Dept. of Chemistry. Title from title page of PDF (viewed 2008/05/28). Includes bibliographical references.

Thesis (Ph. D.)--Georgia State University, 2008. / Title from file title page. Thomas L. Netzel, Dabney W. Dixon, committee co-chairs; David Boykin, Jerry Smith, committee members. Electronic text (250 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Nov. 20, 2008. Includes bibliographical references.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed June 26, 2009). PDF text: viii, 99 p. : ill. (some col.) ; 22.5 Mb. UMI publication number: AAT 3350441. Includes bibliographical references. Also available in microfilm and microfiche formats.