水产调味品中挥发性盐基氮的测定

Determination of total volatile basic nitrogen in aquatic flavouring

为提高水产调味品中挥发性盐基氮测定的效率,对国标GB/T 5009.44-2003中的半微量定氮法进行了改进:用高氯酸溶液替代水来浸溶样品;用氢氧化钠溶液加消泡剂替代了氧化镁混悬液;用自动凯氏定氮仪替代半微量蒸馏装置和半微量滴定管。用改进的方法测定以市售蚝油和虾酱为基质的加标样品,回收率在98.82%～101.26%之间,相对标准偏差在0.80%以下。检测数据与GB/T 5009.44—2003中的半微量定氮法相比,无显著性差异。结果表明,改进的方法是一种简便、快捷、精确的水产调味品中挥发性盐基氮的测定方法。

To raise the efficiency of total volatile basic nitrogen（TVBN） in aquatic flavouring,semimicro quantitative nitrogen method in GB/T 5009.44-2003 was improved as follows： perchlorate acid was used for sample extraction instead of water;sodium hydroxide solution and defoamer was used instead of magnesium oxide suspension;semimicro distillation apparatus and semimicro burette were replaced by automatic automatic nitrogen analyzer.The improved method was applied to measure spiked sample with commercial oyster sauce and shrimp paste as substrate,the recovery was between 98.82% and 101.26%,the relative standard deviation was below 0.80%.The test data of improved method had no significant difference compared with the recovery of semimicro quantitative nitrogen method in GB/T 5009.44-2003.The results showed that improved method was a simple,quick and accurate determination method of TVBN in aquatic flavouring.