Maillard products

Magstream Mahogany acids Mahogany sulfonate Maillard products Maillard reaction... 

Maillard products are not only formed during cooking and other heat processing of foods, but also accumulate in some products that are rich in proteins and reducing sugars, e.g. condensed milk during months of storage at... 

Gradients employed for the HPLC analysis of Maillard products and physiological cross-links. 

The 328/378- and 370/440 fluorescences are characteristic for pentosidine and Maillard products, respectively (Dyer et al., 1991b) while the 317/407 fluorescence indicates dityrosine formation (Huggins et al., 1993). 

Cross-link and Maillard product contents of sound and carious dentin of extracted teeth. ... 

Interestingly, sound human dentin contained a more or less constant level of the advanced Maillard products, pentosidine and car-boxymethyllysine, irrespective of age (fable 3). Alfhough human denfin collagen is not turned over and the advanced products should thus increase during life, we suggesf fhaf fhe Maillard reacfion occurs in pre-denfin collagen, but is halted upon mineralization. ... 

In Chapter 5, it is concluded that release of intracellular bacterial metabolites after cell lysis may have been responsible for fhe increases in advanced Maillard products. Lysis of bacteria can deliberately be induced by, for example, lysogenic enzymes and phages. In addifion fo fhe direcf targeting of cariogenic microorganisms, lysis could thus contribute indirectly to caries arrestment by causing an extensive Maillard reaction. However, the problem of the concomitant unaesthetic discoloration will need to be considered before practical application becomes feasible. 

Unavailable N Acid detergent Kjeldahl nitrogen on ADF residue Maillard products plus lignified N... 

Human perception of flavor occurs from the combined sensory responses elicited by the proteins, lipids, carbohydrates, and Maillard reaction products in the food. Proteins Chapters 6, 10, 11, 12) and their constituents and sugars Chapter 12) are the primary effects of taste, whereas the lipids Chapters 5, 9) and Maillard products Chapter 4) effect primarily the sense of smell (olfaction). Therefore, when studying a particular food or when designing a new food, it is important to understand the structure-activity relationship of all the variables in the food. To this end, several powerful multivariate statistical techniques have been developed such as factor analysis Chapter 6) and partial least squares regression analysis Chapter 7), to relate a set of independent or "causative" variables to a set of dependent or "effect" variables. Statistical results obtained via these methods are valuable, since they will permit the food... 

The most practical method for preventing WOF in meat products is to add antioxidants prepared from natural precursors such as sugars and amino adds by heating them to produce constituents that not only act as antioxidants but serve to enhance meaty flavor as well. The resulting Maillard products have been known to have antioxidant activity in lipid systems (6-8). It is assumed that the antioxidative property of the Maillard reaction is assodated with the formation of low molecular weight reductones and high molecular weight melanoidins (6, 7, 9-13). 

Erbersdobler, H.F. and Dehn-Muller, B. (1989) Formation of early Maillard products during UHT treatment of milk, in Heat-induced Changes in Milk (ed. P.F. Fox), Bulletin 238, International Dairy Federation, Brussels, pp. 62-7. 

Another major problem associated with the extraction of DNA from archaeological specimens is that the procedure often co-extracts impurities that can later complicate, or prevent, the study of the extracted DNA by inhibiting PCR amplification (reviewed by 5). Commonly encountered inhibitory substances found in aDNA extracted from teeth, bones, mummified tissue, and coprolites include humic acids, ftilvic acids, tannins, porphyrin products, phenolic compounds, hematin, and collagen type I (37—42). The formation of Maillard products, commonly encountered in coprolite samples, can also prevent PCR amplification by causing DNA to become inaccessibly trapped in these sugar-derived condensation products (12). As the negative results in many aDNA studies are attributed to the presence of PCR inhibitors, our extraction method outlined below pays particular attention to the problem and offers a simple test for the presence of PCR inhibitors in DNA extracts. 

Thus, according to our results, the crumbs have only slight mutagenic activity as compared to other heat-treated and Maillard products described in the literature (8). 

Our results confirm the antioxidative effect of some Maillard products. The low toxicity of these products may permit using them in certain food products (e.g. in sausages) as mild antioxidants of natural origin (5). 

Our experiments on the mutagenicity of these materials revealed that a water extract of the crumbs did not give a positive Ames test. On the other hand the ethanol extract after distillation produced reverted colonies in the range of the positive control (2-AF) with the most sensitive strains, but only without metabolic activation. The Maillard products responsible for mutations seemed to be metabolized in the living organism. In view of our experiments and the present international evaluation on heat-processed foods, the crumbs present no more detrimental risk to human health than other heat-processed foods, when consumed. 

The model experiments on the antioxidative effect of crumbs revealed the potential ability of the soya-crumb to prevent lipid oxidation in certain foods. The mild acid medium of meat products seems to be favorable for fulfilling this hope. However, further investigations in food products are necessary to obtain a decisive answer. As the case of milk crumb shows, a Maillard product is not necessarily an antioxidant. 

Toasted and browned foods are rich in products of the Maillard reaction. Much effort has been devoted to investigating the effect of the Maillard reaction on protein quality, flavor, and aroma. Recently the influence of Maillard products on metal metabolism has also been investigated. 

The overestimation in the case of the less damaged samples can be explained by the fact that e.g. the "early" Maillard product... 

The genetic activity of pure synthetic Maillard products has also been studied. 2-Methylpyrazine, 2-ethylpyrazine, 2,5-di-methylpyrazine and 2,6-dimethylpyrazine all induced a significant increase in chromosome aberrations in Chinese hamster ovary cells... 

Thiazoles are somewhat unique among the Maillard products because they contain nitrogen and sulfur atom in same ring. The presence of thiazole... 

Formation of Amino Acid Specific Maillard Products and Their Contribution to Thermally Generated Aromas... 

Amino acid specific Maillard products were isolated from the extracts by preparative GC or HPLC and identified by MS-, IR-, 1 H- and c-NMR-spectroscopy. Proline derived components are important constituents in bread, malt and beer. More than 120 proline specific Maillard products were characterized. Cysteine and methionine derived components were predominant in roasted coffee and meat flavors. Thirty cysteine- and twenty methionine-specific Maillard products were identified for the first time. 

Components 2 5 and 1 2 were first detected in wort, which was heated above 140 °C. Beer, produced by this process, possessed a bitter aftertaste. Compound 3. was recently identified as a reactive intermediate, which decomposed very soon even by storage at -20 °C. On heating L-proline and monosaccharides at 150 °C for 1.5 h all compounds increased ten to fiftyfold and 2,3-dihydro-1H-pyrrolizines and di- and tetrahydro-1H-azepines were characterized as major components. On roasting L-proline and monosaccharides (or sucrose) pyrrolidines and azepinones predominate among the Maillard products. These compounds were also formed by heating pyrrolidine and glucose at 100 "C. Azepinones and certain pyrrolin-derivatives possess extreme bitter taste and thresholds of 5 - 10 ppm ( 3, 5 ). ... 

Formation of Amino Acid Specific Maillard Products... 

---