Glucose model

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. 

Figure 1 Main components from proline/glucose model system, depending on pH-value...

In the cysteine/glucose model experiments glucose reduc-tone, acetylformoin, furaneol and cyclotene were detected as major constituents indicating that the 1-deoxy-osone route is operative at pH-values o 5 to 7. As main component we identified by MS, IR- and H-NMR-spectroscopy 4-hydroxy-2,5-dimethyl-3(2H)thiophenone. Obviously this compound is less reactive than the corresponding norfuraneol derivative. Thiofuraneol is also formed from glucose/reductone, acetylformoin and furaneol as demonstrated in model experiments. Surprisingly, it is not formed in cysteine/rhamnose experiments, where furaneol is a major compound. In addition 2-acetyl-4-thiolanone and 5-hydroxymethyl-2-methyl-3-thiolanone were identified for the first time as cysteine specific products. 

Figure 9 Reaction scheme leading to the major products of the cysteine/glucose model experiments...

H. D. Stahl and T. H. Parliment, Formation of Maillard products in the proline-glucose model system high-temperature short-time kinetics, in Thermally Generated Flavors Maillard, Microwave, and Extrusion Processes, T. H. Parliment, M. J. Morello, and R. J. McGorrin (eds), American Chemical Society, Washington, DC, 1994, 251-262. 

V. Fogliano, S. M. Monti, T. Musella, G. Randazzo, and A. Ritieni, Formation of coloured Maillard reactionproducts in a gluten-glucose model system, Food Chem., 1999, 66, 19-25. 

P. Bersuder, M. Hole, and G. Smith, Antioxidants from a heated histidine-glucose model system. Investigation of the copper(II) binding ability, J. Am. Oil Chem. Soc., 2001, 78, 1079-1082. 

Figure 1 Schematic diagram of the a- and /3-anomers of 4,6-0-benzylidene-1 -metoxy-D-glucose (1,2) and of 4,6-0-methylidene-1-metoxy-D-glucose model compounds (3, 4).

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. 

It has been identified in the products of thermal degradation of cysteine and xylose in tributyrin (Ledl and Severin, 1973). It was found in a heated cysteine/glucose model system by Sheldon et al (1986) and in serine/threonine/sucrose model systems (as well as in coffee) by Baltes and Bochmann (1987a). Silwar and Tressl (1989) studied a model reaction involving heating cysteine and methionine with 2-furaldehyde (1.63) under roasting conditions and they found that an important part of the aldehyde is reduced to furfuryl alcohol. 

It is formed in the thermal degradation of glucose (Heyns et al., 1966a Fagerson, 1969). It has been found in a heated proline/glucose system by Brule et al. (1971), in a cysteine/glucose model system by Sheldon et al. (1986), and in threonine/serine/sucrose models by Baltes and Bochmann (1987a). 

Furoic acid is formed in the thermal degradation of glucose (Fagerson, 1969). It has been found in a heated cysteine/glucose model system (Sheldon et al., 1986). 

It was found in a heated cysteine/glucose model system (Sheldon et al., 1986). 

It has been found in the reaction of cysteine (not cystine) with pyruvaldehyde (Kato et al., 1973a), in a heated cysteine/glucose model system (Sheldon et al., 1986), in a cysteine/xylose model (Tressl, 1989), in a cysteine/ribose system, being one of the most important thiophene derivatives, the most important compounds being the two fur an derivatives, 2-furanmethanethiol (1.128) and 2-methyl-3-furanthiol (1.120) (Whitfield et al., 1988). 

It is present in the pyrolysis products of serine (Merritt et al., 1970) and has been found in a heated cysteine/glucose model system (Sheldon et al., 1986), in a model with serine and threonine with and without sucrose (Baltes and Bochmann, 1987c). (Note all the alkylpyrazines from 0.1 to 0.15 have been identified in this last publication in coffee as well as in the heating products of serine and threonine with or without sucrose, therefore we will mention it again after 0.15). 

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). 

Mitton, K. P, Dzizloszyh.ski, T, Wierheim, J., Trevithick, J. R., and Sivak, J, (1990). Modeling conical cataractogenesis. X. Evaluation of lens optical function by computer-based image analy.si.s using an in vitro rat lens elevated glucose model. 

Lertittikul, W., Benjakul, S., and Tanaka, M. Characteristics and antioxidative activity of Maillard reaction products from a porcine plasma protein-glucose model system as influenced by pH, Food Chem., 100, 669, 2007. 

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. 

Zhang, Y., and Zhang, Y. 2008. Effect of natural antioxidants on kinetic behaviour of acrylamide formation and elimination in low-moisture asparagine-glucose model system, /. Food Eng., 85 105-115. 

HD Stahl, TH Parhment. Formation of Maillard Products in the Proline-Glucose Model System—High-Temperature Short-Time Kinetics Thermally Generated Flavors. Washington, D.C. American Chemical Society, 1994, pp... 

---