基于美拉德反应分析加工过程中酱牛肉风味物质变化

Changes in Flavor Substances of Sauced Beef during Processing Based on the Maillard Reaction

为探究不同加工过程中酱牛肉风味物质的变化,以A_(294)_(nm)和A_(420nm)分别代表中期、末期美拉德产物的形成量,从美拉德反应角度分析超声-分段煮制(CF)、分段煮制(F)以及传统煮制(CT)对酱牛肉风味的影响。结果显示,CF组和CT组的A_(294)_(nm)在煮制0.5h时存在显著差异(P<0.05),煮制2、4h时无显著差异(P>0.05)。煮制0.5、4h时F组的A_(294nm)和A_(420nm)显著高于CT组和CF组(P<0.05)。荧光强度检测结果表明,CF组荧光强度最高。蛋白二级结构分析结果表明,与CT组相比,CF组和F组可提高酱牛肉β-折叠相对含量,降低α-螺旋相对含量,α-螺旋解螺旋导致内部疏水基团暴露,因此提高了样品的表面疏水性和荧光强度。超高效液相色谱-质谱分析结果显示,CT、F、CF组分别筛选出103、167、200种差异代谢物,CF组中产生了大量的氨基酸、二肽、核苷以及杂环类化合物;气相色谱-质谱分析结果也表明,超声-分段煮制、分段煮制可促进酱牛肉挥发性风味物质产生。综上,超声-分段煮制、分段煮制可促进美拉德反应的进行,改善酱牛肉风味。

In this study,sauced beef was prepared by three different cooking processes:ultrasonic-assisted stepwise cooking(CF),stepwise cooking(F)and traditional cooking(CT).In order to investigate changes in the flavor substances of sauced beef during different cooking processes,the effect of the three cooking processes on the flavor of sauced beef were analyzed from the perspective of the Maillard reaction.Absorbance at 294 nm(A_(294 nm))and 420 nm(A_(294 nm)),which can reflect the amount of Maillard reaction products(MRPs)formed in the middle and late stages,respectively,were measured.The results showed significant differences in A_(294 nm) between the CF and CT groups at 0.5 h of cooking(P<0.05),but no significant differences between the CF and CT groups at 2 and 4 h(P>0.05).A_(294 nm) and A420 nm were significantly higher in the F group than in the CT and CF groups at 0.5 and 4 h.The CF group had the highest fluorescence intensity.Protein secondary structure analysis indicated an increase in the relative content ofβ-sheet and a decrease in the relative content ofα-helix in the CF and F groups compared with the CT group;α-helix unfolding led to the exposure of intramolecular hydrophobic groups,thereby increasing the surface hydrophobicity and fluorescence intensity.Ultra-high performance liquid chromatography-mass spectrometry(UPLC-MS)identified 103,167,and 200 differential metabolites in the CT,F,and CF groups,respectively,and a large number of amino acids,dipeptides,nucleosides,and heterocyclic compounds were produced in the CF group;gas chromatography-mass spectrometry(GC-MS)results showed that CF and F promoted the production of volatile flavor substances in sauced beef.The above results indicated that both cooking processes could promote the Maillard reaction and consequently improve the flavor of sauced beef.