基于气相色谱-质谱技术与多元统计分析咸蛋黄热加工中的异味组分

Analysis of Odor Components in Salted Egg Yolk during Thermal Processing Using Gas Chromatography-Mass Spectrometry and Multivariate Statistical Analysis

为明确热加工中咸蛋黄产生的异味化合物,采用感官评价、气相色谱-质谱联用技术结合聚类分析、正交偏最小二乘判别分析和主成分分析等多元统计分析方法对咸蛋黄在热加工中的异味物质展开研究。通过感官定量描述分析明确无异味咸蛋黄和异味咸蛋黄样品具有风味轮廓差异,确定部分咸蛋黄在热加工中存在明显异味。聚类分析显示6组咸蛋黄样品被清晰地分成两类,与感官评价结果一致。进一步对无异味和异味咸蛋黄挥发性物质相对含量采用正交偏最小二乘判别分析,得到33种变量投影重要性值大于1的主要差异组分,其中以醛类及醇类差异最为显著。最后,通过主成分分析筛选出咸蛋黄中和酸臭味正相关的挥发性化合物,并结合香气活度值大于1确定正己醛、正戊醛、1-辛烯-3-醇、反,反-2,4-癸二烯醛、苯乙烯、二甲基二硫醚以及2-壬酮为咸蛋黄热加工中的主要异味化合物。该结果为热加工后咸蛋黄的风味特征及可能产生的异味组分解析提供参考,并为咸蛋黄风味评价提供科学依据。

Odor compounds produced in salted egg yolk during thermal processing were identify by sensory evaluation and gas chromatography-mass spectrometry(GC-MS)combined with multivariate statistical analysis such as hierarchical cluster analysis(HCA),orthogonal partial least squares-discriminant analysis(OPLS-DA)and principal component analysis(PCA).By using quantitative descriptive sensory analysis,it was found that there was a significant difference in the flavor profile between egg yolk samples with and without unpleasant odor,and it was determined that some egg yolks had obvious off-flavor during hot processing.Cluster analysis showed that the six groups of salted egg yolk samples were clearly divided into two categories,which was consistent with the sensory evaluation results.Furthermore,OPLS-DA identified 33 major differential components with variable importance in the projection(VIP)scores greater than one between samples with and without unpleasant odor,and aldehydes and alcohols were the most significant differential components.Finally,the volatile compounds showing a positive correlation with sour odor were screened by PCA,and n-hexanal,n-valeraldehyde,1-octen-3-ol,trans,trans-2,4-decadienal,styrene,dimethyl disulfide and 2-nonone were identified due to their odor activity values(OAV)greater than one as the major odor compounds of salted egg yolk during thermal processing.The results provide a reference for analysis of the flavor characteristics and possible off-flavor components of salted egg yolk after thermal processing and provide a scientific basis for accessing the quality of salted egg yolk.