Maillard reactions consequences

R. Ikan, Ed, The Maillard Reaction Consequences for the Chemical and Life Sciences, John Wiley Sons, New York, 1996. 

Ho C-T (1996) Thermal degradation of Maillard aromas. In Ikan R (ed) the Maillard reaction Consequences for the chemical and life sciences. Wiley, Chichester, UK, pp 27-53... 

Figure 2.7. A schematic representation of the Maillard reaction. Adapted with permission from Ikan, R. Y., Rubinsztain, Y., Nissenbaum, A., and Kaplan, I. R. (1996). Geochemical aspects of the Maillard reaction. In The Maillard Reaction Consequences for the Chemical and Life Sciences, Ikan, R., ed., John Wiley and Sons, Chichester, UK, 1-25.

The Maillard reaction is likely to take on additional significance with the introduction of many new protein and peptide pharmaceuticals. For example, Tarelli et al. have demonstrated that lysine vasopressin undergoes rapid glycation in the presence of reducing sugars in both aqueous and solid formulations and that the N-terminal adduct can form rapidly even at — 20°C [52], A textbook that deals with the consequences for the chemical and life sciences of the Maillard reaction has been published [53]. 

The formation of oxygen-containing heterocyclic compounds is also a consequence of the Maillard reaction. Amines and amino acids have a catalytic effect upon the formation of 2-furaldehyde (5), 5-(hydroxy-methyl)-2-furaldehyde (11),2-(2-hydroxyacetyl)furan (44),2 and 4-hy-droxy-5-methyl-3(2//)-furanone (111) (see Ref. 214). This catalytic effect can be observed with several other non-nitrogenous products, including maltol. The amino acid or amine catalysis has been attributed to the transient formation of enamines or immonium ions, or the 1,2-2,3 eno-lization of carbohydrates. Of interest is the detection of A -(2-furoyl-... 

It has been suggested that some products of the Maillard reaction are toxic and/or mutagenic but such effects are, at most, weak and possibly due to other consequences of browning, e.g. metal binding. 

Adrian, J. Nutritional and physioloical consequences of the Maillard reaction. World Rev. Nutr. Diet. 1974, 19, 71-122. 

Mutagens in Cooked Foods Possible Consequences of the Maillard Reaction... 

In the presence of an equimolar quantity of inorganic phosphate it was found that the formation and the conversion of the ARP are enhanced, resulting in a relatively low overall concentration of the ARP, and consequently in a high yield of Maillard reaction products, i.e. the results mentioned above showed a high conversion of the starting materials at higher pH-values. 

Production of water is one of the symptoms of the Maillard reaction (see Chapter 1). In particular, sugar dehydration (Reaction C of the Intermediate Stage) produces a substantial proportion of water, which, in theory, has several potential consequences. If a food is of low aw, the moisture may be sufficient to encourage microbial growth. At low flw, an increase in moisture would also increase the rate of browning. It could contribute to a deterioration of texture as well. Although these aspects need to be borne in mind, they are by no means the primary considerations. 

The possible consequences of a drop in pH are manifold. The pH greatly affects the mechanism of the Maillard reaction itself (see Chapter 2), it affects microbial activity, and it may cause polymeric material, particularly proteins, to lose solubility and thus alter texture. 

Nutritional Effects Due to the Blockage of Lysine. The most important Maillard reaction in food proteins occurs with the c-amino group of lysine. Since lysine is an essential amino acid, nutritional consequences can be expected. These depend on the chemical structure of the lysine derivatives formed. 

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