平行因子结合二维荧光光谱相关技术解析丙二醛诱导熟肉糜氧化过程

采用前表面三维同步荧光光谱、平行因子和二维相关技术研究丙二醛诱导熟肉糜氧化过程的荧光特征。发现丙二醛熟肉糜体系有两个特征同步荧光峰，分别是色氨酸残基的荧光特征(Ex292 nm、Δλ50 nm)和丙二醛蛋白结合物的荧光特征(Ex400 nm、Δλ70 nm);平行因子分析表明Δλ为50和70 nm的同步荧光光谱分别为第一、第二主成分，分别对应的是色氨酸残基的荧光特征和丙二醛蛋白结合物的荧光特征;丙二醛诱导熟肉糜氧化过程中，随着时间的延长，色氨酸残基特征同步荧光强度逐渐减弱，丙二醛蛋白结合物特征同步荧光强度逐渐增强;二维相关分析表明，色氨酸残基荧光强度变化速率快于丙二醛蛋白结合物的荧光强度变化速率。

Use of Parallel Factor and Two Dimensional Fluorescence Spectroscopy Correlation Technique for Measurement of Reaction between MDA and Cooked Ground Meat

The fluorescence characteristics of oxidation reaction between MDA and cooked ground meat were analyzed by front face three dimensional synchronous fluorescence spectroscopy, parallel factor and two dimensional correlation technique. The results showed that the reaction system has two synchronous fluorescence peaks, one is Ex 292 nm and Δλ 50 nm, assigned to the fluorescence characteristics of tryptophan residues in proteins; the other is Ex 400 nm, Δλ 70 nm, corresponding with the fluorescence characteristics of MDA-protein adducts formed during oxidation; The synchronous fluorescence landscape was analyzed using PARAFAC. The loading profiles of 1st and 2nd components had an optimal λ 50 and 70 nm, respectively. During oxidation reaction, the synchronous fluorescence intensity of tryptophan gradually decreased, while the synchronous fluorescence intensity of MDA-protein adducts gradually increased. Two dimensional correlation synchronous fluorescence spectroscopy technique showed that the variation ratio of fluorescence intensity of tryptophan preceded that of MDA-protein adducts.