Glucose-glycine model systems

Spray drying is extensively used in industry, and therefore spray drying a glucose-glycine model system has specific technological relevance. Compounds 19 and 20 were tentatively identified in the product.174... 

R. C. Borrelli, V. Fogliano, S. M. Monti, and J. M. Ames, Characterization of melanoidins from a glucose-glycine model system, Eur. Food Res. Technol., 2002, 215, 210-215. 

Y. Yoshimura, T. Iijima, T. Watanabe, and H. Nakazawa, Antioxidative effect of Maillard reaction products using glucose-glycine model system, J. Agric. Food Chem., 1997, 45, 4106 1109. 

Effect of Acetate Concentration on Maillard Browning in Glucose-Glycine Model Systems... 

The formation of brown pigments via the Maillard reaction, especially in model systems (e.g. glucose-glycine), usually follows zero-order kinetics, but the loss of reactants has been found to follow first- or second-order kinetics in foods and model systems. Activation energies of 109, 116 and 139 kJ mol-1 have been reported for the degradation of lysine, the formation of brown pigments and the production of hydroxymethylfurfural (HMF), respectively. 

Haffenden, L. J. W., and Yaylayan, V. A. (2005). Mechanism of formation of redox-reactive hydroxylated benzenes and pyrazine in 13C-labled glycine/D-glucose model systems. /. Agric. Food Chem. 53, 9742-9746. 

Mundt el al.n9 have adapted the above scheme for the maltose-glycine system (pH 5.5, 70 °C). Multiresponse modelling gave excellent fits for the time course of the concentrations of glucose, melanoidins (A470, number of maltose molecules incorporated from U-14C-labelled maltose), 3-DH (as quinoxaline derivative), maltose, and SIV (in maltose-glycine-SIV systems). 

The objective of this work was to investigate the effect of acetate buffer on the browning glucose-glycine in model systems. 

YAYLAYAN, V. A. and KAMINSKY, E. (1998). Isolation and structural analysis of Maillard polymers caramel and melanoidin formation in glycine/glucose model system. Food Chemistry, 63, 25-31. 

Its formation from rhamnose heated with piperidine acetate in ethanol, under the same conditions that produced amino-hexose-reductones from glucose and other hexoses, was described as early as 1963 by Hodge et al., who confirmed the structure by IR and NMR data and proposed a formation pathway. The formation from Amadori intermediates was been reviewed by Vernin (1981). Numerous model systems have confirmed that it is one of the main Maillard-reaction products. For instance we will mention the formation from L-rhamnose and ethylamine (Kato et al., 1972) and from pentose/glycine or alanine, whose mechanism was proposed by Blank and Fay (1996) and Blank et al. (1998), from the intermediate Amadori compound, /V-(l-deoxy-D-pentos-l-yl)glycine. Furaneol is also formed by recombination of... 

Dawes and Edwards (1966) isolated it from the volatiles obtained by heating a mixture of D-fructose and glycine or L-3-phenylalanine. Wang et al. (1969) presented a model reaction in which the product of condensation of pyruvaldehyde with any amino acid degraded by a Strecker reaction can form an aminoketone which by subsequent steps of self-condensation and oxidation formed 2,5-dimethylpyrazine (Wang et al., 1969 Manley et al., 1974). It was found in a heated cysteine/glucose model system (Sheldon et al., 1986). 

Yen, G. C. and Chau, C. F. 1993. Inhibition by xylose-lysine Maillard reaction products of the formation of MelQx in a heated creatinine, glycine, and glucose model system. Biosci. Biotech. Biochem. 57 664-665. 

Owing to the complexity of the Maillard reaction, model systems containing only one reducing sugar and one amino acid are often chosen because they are simpler systems than foods. Research has shown that even in simple reaction systems, for example in glucose and glycine solutions, many tens of reaction products are formed. Therefore, even in such simple systems, the Maillard reaction... 

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