腌制咸菜中亚硝酸盐含量测定.doc

腌制咸菜中亚硝酸盐含量测定
腌制咸菜中亚硝酸盐含量的测定
摘要:
目的:建立测定腌制蔬菜中亚硝酸盐含量的方法。方法:在弱酸性溶液中亚硝酸盐与对氨基苯磺酸反应生成的重氮化合物,重氮化合物再与盐酸萘乙二胺偶联生成紫红色的偶氮染料,用分光光度法测定。结果:经过校正,亚硝酸盐含量x (μg) 与吸光度A 之间在λmax = 533nm 处,具有良好的线性关系。利用此方法所测定的腌制蔬菜中亚硝酸盐的含量随时间有一定变化规律。结论:用分光光度法测定腌制咸菜中亚硝酸盐的含量,方法简单、方便、快捷、实用,可对食品中亚硝酸盐含量的测定中推广应用。
关键词:腌制咸菜;亚硝酸盐测定;分光光度法
The determination of the nitrite content of pickled vegetables Rongyanjun( Major biotechnique,grade 2007,Ocean University of China) Aim To establish a method for determining the content of the nitrite in pickled vegetables . Methods Nitrite react with 4-aminobenzenesulfonic acid in weak acidic media to produce 4-sulfobenzenediazonium , which reacted with N′- ( nap ht halen -1-yl) eth- ane-1 ,2-diamine hydrochloride to produce a red pound , the pound was detected byspect rop hotometer . Results The calibration graph for aqueous procedure was obtained by plotting ab-sorbance values at 533 nm against nit rite concent ration. The content level of nitrite in the pickled vegetables we used has some disciplines. Conclusion
The met hod is accurate , rapid , simple , can be applied in determining the nit rite content of the pickled vegetables .
Key words: pickled vegetables; nitrite determination; spect rop hotometer 1引言
腌制蔬菜是利用食盐的高渗透压作用、微生物的发酵作用、蛋白质的分解作用及其它一系列的生化作用,抑制有害微生物的活动和增加产品的色、香、味的加工过程。蔬菜易富集硝酸盐,在腌制过程中,
由于有害微生物及硝酸还原酶的作用,硝酸盐会转化为亚硝酸盐。亚硝酸盐是一种毒性很强的致癌物,它能与胺类物质生成亚硝胺而致癌,摄入会对人体造成危害,更为严重