Maillard Reaction Products: Uptake, Metabolic Transit and Selected Parameters of Biopotency and Safety

摘要

During thermal processing of foods, a number of products are formed in the Maillard Reaction (MR) between amino groups and reducing sugars, whose nutritional importance was investigated since more than fifty years. These and further results obtained demonstrated very clearly that apart from total destruction of amino acids specific derivatives or crosslinking products are formed which influence the bioavailability of amino acids and affect also the overall digestion of the protein. To some extent, also adverse or toxic compounds are supposed to be formed. With the detection of furosine as indicator of the Amadori compounds fructoselysine, maltuloselysine and lactuloselysine, a quantitative calculation of lysine damage and of the remaining amount of available lysine was feasible for the first time. The chemical structures of the early formed Amadori products are known, but products of the more advanced stage of the MR, like the brown coloured me-lanoidins, are poorly characterised so far. Figure 1 gives an overview on the main stages of the Maillard reaction with two examples of reaction products mentioned later. Amadori products were found in quite high concentrations in processed milk proteins like that of condensed milk, scorched dried skim milk, some infant milk formulas and moreover in bread, biscuits and chocolate [for details see: 10, 11, 121. Melanoidins occur e.g. in roasted coffee, in bread crust, in dark coloured beer and in several other intensively browned foods. Although the formation of MR products like FL or CML in processed dairy foods is well-known, comprehensive data about the daily intake of these compounds is still missing. Very roughly, the average daily intake of FL and CML can be estimated at ～500 mg FL and ～10 mg CML.