为建立秋刀鱼鲜度快速评定方法，研究了秋刀鱼于4 ℃条件下感官评分、TVB-N、TBARS、细菌总数以及电子鼻检测信号的变化情况。结果表明，秋刀鱼在冷藏过程中感官评分呈下降趋势，贮藏前期气味劣化是总评分降低的主导因素；TVB-N值在贮藏前期变化较小，第5 d开始呈显著增加（p<0.05），11 d时接近0.30 mg/g的界限值；TBARS含量在贮藏过程中迅速增加；细菌总数的变化与TVB-N值的变化趋势较为一致，第11 d时接近7.0 Log10 CFU/g的界限值。综合感官、生化和微生物指标，秋刀鱼在4±1 ℃条件下一级鲜度可保持3 d，二级鲜度可保持至第7 d，货架期为9~11 d。冷藏过程中秋刀鱼样品在PCA的二维图形上倾向于聚类分布，且特征区域没有重叠，电子鼻可以很好的表征秋刀鱼的鲜度变化，同时与感官评分、生化指标以及微生物指标指示的鲜度等级基本一致。研究结果将为秋刀鱼鲜度的快速评定提供技术参考。

To analyze changes in the quality of Cololabis saira during refrigerated storage and to establish a rapid method for assessing its freshness, the sensory scores, TVB-N values, TBARS values, total bacteria count, and electronic nose measurement signals of C. saira under storage at 4 ℃ were determined. The results showed that the sensory score declined during storage, mainly because of smell degradation during the initial period. Although changes in TVB-N values were relatively small in the first three days, they increased significantly (p<0.05) from the fifth day and reached 0.3 mg/g on day 11, along with the generation of volatile substances such as aldehydes, ketones, and acids. TBARS levels showed a rapid increase and caused a rapid decline in odor scores. The total bacteria count increased rapidly from the fifth day and reached 7.0 Log10 CFU/g on day 11, which was consistent with the TVB-N values. According to the sensory, physical, chemical, and microbiological indicators, C. saira had first-grade freshness in the first three days and second-grade freshness until day 7; the shelf life was estimated to be 9~11 d. The two-dimensional graphical result of the principal component analysis (PCA) revealed a clustered distribution with no overlaps in features. The electronic nose could fully characterize the changes in freshness of C. saira during refrigerated storage, and the freshness level estimated thus was consistent with that characterized by sensory evaluation, physicochemical indicators, and microbiological indicators. These results could serve as a technical reference for quick assessment of fish freshness.

国家自然科学基金项目（31301587）