以生物胺变化评价冷藏罗非鱼片腐败进程

为了探讨生物胺指标评价鱼肉腐败进程的可能性及其安全范围,应用反相高效液相色谱法测定冷藏罗非鱼片贮藏过程的生物胺变化,用以判断鱼片的腐败进程。结果表明:新鲜鱼片初始单胺和多胺总量较高,二胺总量很低。贮藏过程中单胺和多胺波动变化并呈下降趋势,尸胺、腐胺含量快速增加成为主要生物胺。含有尸胺+腐胺的二胺、生物胺指数、总生物胺等指标与其两者增长趋势相似。相关分析表明尸胺、腐胺、二胺、生物胺指数、总生物胺与贮藏时间、微生物数量和氨基态氮具有高度相关性。经回归分析表明假单胞菌、肠杆菌的增长与尸胺、腐胺具有重要的对应关系。尸胺、腐胺和二胺可简便有效评价鱼片腐败进程;但综合考虑组胺和酪胺的毒性,则生物胺指数(BAI)更适用,冷藏罗非鱼片生物胺指数的初步判别范围为:<20mg/kg,新鲜;20～40mg/kg,可接受;>40mg/kg,腐败。该研究为冷藏罗非鱼片生物胺的限量标准提供数据参考。

Assessment of spoilage progress for chilled tilapia fillets according to biogenic amines changes

In order to explore the possibility and safety ranges of biogenic amines indicators for evaluating fish spoilage progress, reversed-phase high-performance-liquid-chromatography method was employed to detect the biogenic amines changes of tilapia fillets during chilled storage. The results showed that initial content of monoamines and polyamines in fresh fillets was high, and those of diamines was low. During chilled storage, monoamines and polyamines content showed fluctuating and decreasing trend. Cadaverine and putrescine content were decreased quickly and became the major biogenic amines. The cadaverine and putrescine relative indicators like diamines, biogenic amines index and total biogenic amines showed a similar increasing trend of cadaverine and putrescine. The correlation analysis showed that there were high correlation among cadaverine, putrescine, diamine, biogenic amines index, total biogenic amines with storage time, microbial counts and amine nitrogen. The regression analysis indicated that the relationship among the growth of pseudomonas, enterobacteriaceae and cadaverine and putrescine was inseparable. The indicators of cadaverine, putrescine and diamine could be used for evaluating fillet spoilage progress simply and effectively. Considering the toxicity of histamine and tyramine, biogenic amines index (BAI) were more suitable. The preliminary range of BAI for evaluating spoilage progress of chilled tilapia fillets were as follows: <20 mg/kg, fresh; 20-40 mg/kg, acceptable; >40 mg/kg, spoiled. These results would offer the basic data for standard limits of biogenic amines in chilled tilapia fillets.