亮氨酸与还原糖组成的Maillard模型体系形成异戊醛

Formation of Isovaleraldehyde in the Maillard Model Reaction System Consisting of Leucine and Reducing Sugar

通过正交试验研究反应温度、反应物摩尔比以及pH值对L-亮氨酸与还原糖组成的Maillard模型体系形成异戊醛的影响。当反应温度从100℃上升至140℃,异戊醛的产率增加。对葡萄糖或核糖体系,异戊醛产率随还原糖的用量增加而增加。通常弱酸性或弱碱性的条件比中性的条件更有利于异戊醛的形成。在葡萄糖、果糖、木糖和核糖4种糖中,葡萄糖和果糖体系形成的异戊醛产率更高,而且副产物少。在木糖或核糖大量过量而且温度较高的情况下,主要形成糠醛的副产物。葡萄糖与亮氨酸组成的体系在最佳条件下,得到异戊醛最高产率约为32%;果糖体系形成异戊醛最高产率约21%。

The effects of temperature, reducing sugar/amino acid molar ratio and pH value on the formation of isovaleraldehyde in Maillard reactions between leucine and four reducing sugars such as glucose, fructose, xylose and ribose were investigated by an orthogonal array design involving 9 experiments of three variables at three levels. The yield of isovaleraldehyde increased when the reaction temperature rose from 100 to 140℃. For the Maillard reactions consisting of glucose and ribose, respectively, the yield of isovaleraldehyde increased with the molar ratio of sugar to leucine increasing. The reactions carried out under a slightly acidic or basic condition usually gave isovaleraldehyde in higher yields than those reactions under a neutral condition. Of the four sugars under investigation, glucose and fructose reacted with leucine to give isovaleraldehyde with fewer impurities in much higher yields than xylose and ribose. When a large excess of xylose or ribose reacted with leucine at a relative high temperature, furfural was formed as a major byproduct. Under optimized reaction conditions, the yield of isovaleraldehyde obtained from the reaction of glucose with leucine was about 32%, and fructose gave isovaleraldehyde in about 21% yield.