Wang Yu, Ho Chi-Tang
Department of Food Science, Rutgers University, New Brunswick, New Jersey 08901-8520, USA.
J Agric Food Chem. 2008 Aug 27;56(16):7405-9. doi: 10.1021/jf8012025. Epub 2008 Jul 2.
The caramel-like aroma compound, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) was quantified and verified by HPLC and GC-MS in the Maillard reaction based on methylglyoxal (MG). The reaction was performed in the 0.5 M phosphate buffer by heating MG with or without either glycine or cysteine at 120 degrees C for 1 h. MG alone or MG with cysteine could produce increased level of DMHF with pH increased, whereas MG with glycine had contrary trend. Experiments using a 1:1 mixture of [(13)C6]glucose and [(12)C6]glucose indicate that in the presence of glycine or cysteine, glucose skeleton kept intact during DMHF formation since a 1:1 mixture of [(13)C6]DMHF and [(12)C6]DMHF was formed. Acetylformoin was detected in the glucose with amino acid reaction system as a precursor of DMHF, while in the MG reaction systems, acetylformoin could not be identified. It is suggested different pathways of DMHF formation via MG and glucose.
基于甲基乙二醛（MG）的美拉德反应中，通过高效液相色谱（HPLC）和气相色谱 - 质谱联用（GC - MS）对类似焦糖的香气化合物2,5 - 二甲基 - 4 - 羟基 - 3(2H)-呋喃酮（DMHF）进行了定量和验证。该反应在0.5M磷酸盐缓冲液中进行，将MG与甘氨酸或半胱氨酸一起或不与它们一起在120℃加热1小时。单独的MG或与半胱氨酸一起的MG随着pH值升高可产生更高水平的DMHF，而与甘氨酸一起的MG则呈现相反趋势。使用[(13)C6]葡萄糖和[(12)C6]葡萄糖1:1混合物的实验表明，在存在甘氨酸或半胱氨酸的情况下，由于形成了[(13)C6]DMHF和[(12)C6]DMHF的1:1混合物，葡萄糖骨架在DMHF形成过程中保持完整。在葡萄糖与氨基酸反应体系中检测到乙偶姻作为DMHF的前体，而在MG反应体系中未鉴定出乙偶姻。这表明通过MG和葡萄糖形成DMHF的途径不同。
