利用Flash E-Nose方法探究漂洗处理对鲶鱼鱼糜的脱腥效果

Evaluation of Rinsing for Deodorization of Catfish Surimi by Flash E-Nose

目的:探索不同漂洗方法对鲶鱼碎肉的脱腥效果。方法:测定不同漂洗处理(未漂洗、调配液漂洗和清水漂洗)的鲶鱼碎肉的营养成分,并利用超快速电子鼻(Flash E-Nose)检测在冷藏过程中的挥发性气味物质变化,测定的时间点为p H值的起始点、极限p H值点和鱼肉腐败点,通过对所获数据进行主成分分析,来判断不同漂洗处理对鲶鱼肉的脱腥效果。结果:漂洗后的碎肉蛋白质含量,水分含量均比对照组高,而脂肪含量明显减少,调配液漂洗效果更佳;Flash E-Nose可以将不同漂洗处理的鱼肉样品中的挥发性气味物质很好地分离开来,未漂洗的鲶鱼肉检出醛类、烃类、醇类、呋喃类、三甲胺等成分,它们的协同作用构成了鲶鱼肉的土腥味,而经过漂洗处理能够有效地去除三甲胺。结论:调配液漂洗能够提高鱼肉品质;并且鲶鱼鱼肉中含有较多的腥味成分如2-甲基戊醛、3-甲基-3-磺酰基-1-羟基丁醇和三甲胺等,通过漂洗处理后前2种成分的相对含量明显减少,三甲胺能够被完全去除。所以漂洗能够有效地达到脱腥的效果,调配液漂洗的效果更佳。

Objective: To investigate the effects of different rinsing treatments on the deodorization of minced catfish meat. Methods: The nutritional composition of catfish meat was measured under three different rinsing treatments, i.e., unrinsed(M1, control), rinsed with an aqueous solution of 0.5% sodium bicarbonate and 0.25% sodium pyrophosphate adjusted to p H 6.5(M2) and with distilled water(M3). The changes in odor substances were measured by Flash E-Nose at three time points for p H(i.e., starting, extreme and fish spoilage points) during cold storage. The obtained data were subjected to principal components analysis(PCA), and changes in the main volatile compounds were examined to judge the effectiveness of different rinsing treatments for deodorizing catfish meat. Results: Rinsing resulted in an increase in both protein and moisture contents and a significant reduction in fat content compared with the control group, and M2 was more effective than M3. The Flash E-Nose could detect and distinguish quite well the volatile substances of samples from the three groups. 2-Methyl amyl aldehyde, aldehydes, 3-methyl-3-sulfonyl-1-butanol, trimethylamine(TMA) and other compounds, which synergistically constituted to the fishy odor of catfish, were detected in the control sample. Effective removal of trimethylamine was achieved by rinsing. Conclusions: The quality of the fish can be improved by using the mixed rinsing solution. The major fishy substances existing in catfish flesh are 2-methyl aldehyde, 3-methyl-3-sulfonyl-1 hydroxy butylalcohol and TMA. After rinsing process, the relative contents of 2-methyl aldehyde, 3-methyl-3-sulfonyl-1 hydroxy butylalcohol decrease significantly, and TMA can be removed completely. Therefore rinsing could effectively deodorize catfish meat, especially by using the blended solution.