The Regulation And Mechanism Of A-dicarbonyl Compounds Formation In Model Systems

α-Dicarbonyl compounds(α-DCs)are important intermediates of Maillard reaction which are easily found from carbohydrate-rich or lipid-rich foods especially at high temperature.α-DCs are important precursors of acrylamide,4(5)-hydroxymethyfurfural which are carcinogenity substances produced by Maillard reaction.In this research,the most normal α-DCs(3-deoxyglucosone,glyoxal,methyglyoxal and 2,3-butanedione)were studied among various kinds of which had been found already.In this paper,the model systems of hydrolysed β-Lactoglobulin at different hydrolysing time(6h,12h,18h and 24h)and at different molecular weight(>10kDa,3-10kDa and<3kDa).These modle systems were devided into three parts:modle system ofβ-Lactoglobulin,modle system of peptides and modle system of Lysine.And the heating temperatures were set as 120℃,130℃,140℃,160℃ and 180℃.The regulation and mechanism of a-dicarbonyl compounds was studied.And our results could provide the basic for controlling the hazardous substances.The results showed that with the increase of Maillard reaction temperature,the formation pathway of 3-deoxyglucosone and glyoxal was blocked,resulting in a gradual decrease in the formation of both.However,the yield of 2,3-butanedione was mainly affected by 1-deoxyglucosone pathway,showing a decreasing tendency with the increase of temperature.As the reaction temperature increases,the role of amino compounds is limited.Amino compounds played a catalytic role in the formation of α-DCs.Higher molecular weight peptides catalyze the production of 3-deoxyglucosone,whereas smaller peptides are detrimental to 3-deoxyglucosone production.However,the change of molecular weight of peptides did not affect the formation of glyoxal,methylglyoxal and 2,3-butanedione regularly.By comparing the β-lactoglobulin system,the peptide system and the lysine system,it is found that the peptide system is more conducive to the formation of glyoxal and 2,3-butanedione,but the β-lactoglobulin system more conducive to the formation of methylglyoxal.Among the four variables,Maillard reaction temperature has the most influence on α-dicarbonyl compound.