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硝酸盐、亚硝酸盐主要用作防腐剂与着色剂应用于食品加工生产过程中,但有研究显示过量摄入可能引起中毒或死亡,对其检测方法的研究也处于不断摸索优化阶段。本文主要对硝酸盐与亚硝酸盐的检测方法研究进展进行了综述,并对相关检测方法进行对比介绍。目前,应用较多的检测方法有快速检测法、分光光度法、化学发光法、电化学方法、高效液相色谱法等。其中,快速检测法耗时较短,但不能实现对硝酸盐和亚硝酸盐的准确定量;而光谱法在一定程度上解决定量问题,但该方法检测限普遍较高;电化学方法操作简便,但存在一定的不确定性;众多研究数据显示,色谱法具有操作简单、快速、灵敏度高等特点,在众多领域应用最为广泛,尤其高效液相色谱法最为突出。气相色谱法在其基础上可实现硝酸盐与亚硝酸盐的同时检测。本文也对高效液相色谱法进行重点介绍。 相似文献
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蔬菜中硝酸盐和亚硝酸盐的测定及含量分析 总被引:2,自引:0,他引:2
采用超声提取、活性炭柱脱色和微孔膜过滤等步骤对蔬菜进行预处理,离子色谱法测定蔬菜中硝酸盐和亚硝酸盐含量。探讨不同贮藏条件下4种蔬菜中硝酸盐和亚硝酸盐含量的变化情况。结果表明:无论常温贮藏还是低温贮藏,贮藏7d内,4种蔬菜中硝酸盐含量变化基本上是呈下降趋势,亚硝酸盐含量均呈现先急剧上升后近于平稳的趋势,但常温贮藏的亚硝酸盐含量高于低温贮藏,除韭菜外,其它蔬菜中亚硝酸盐含量均低于限量标准4mg/kg。 相似文献
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蔬菜中硝酸盐、亚硝酸盐提取与测定的研究 总被引:1,自引:0,他引:1
目的:研究蔬菜中硝酸盐、亚硝酸盐对保障人类健康具有重要意义.方法:本实验选择用简便、高效的超声波提取技术提取蔬菜中的硝酸盐和亚硝酸盐,用紫外分光光度法测定其含量.结果:研究表明,利用紫外分光光度法同时测定蔬菜中硝酸盐和亚硝酸盐含量的方法简单、快速、选择性好.结论:硝酸盐测定的相对误差在-2.52%~1.14%之间,亚硝酸盐测定的相对误差在1.98%~4.26%之间,符合定量测定要求. 相似文献
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对不同温度、容器等贮存条件下蔬菜及菜汤中NO3-和NO2-含量状况的研究。结果表明:不论是在新鲜蔬菜还是菜汤中,这两种有害物质的含量均随贮存温度的升高而相应增加,且含盐菜汤中的含量高于无盐菜汤;在同种温度条件下,3种不同质地容器贮存的菜汤中NO3-特别是NO2-的含量差异较大,均为铝容器>不锈钢容器>铁容器。 相似文献
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测定菜蕨、刺苋、苣荬菜等3种野菜不同发育阶段叶中的硝酸盐、亚硝酸盐和Vc的含量,实验结果分析可知:提琴头期、幼叶期、成熟叶期的菜蕨和幼苗期、营养生长期、果期的苣荬菜为一级蔬菜,可生食、盐渍和熟食;半成熟叶期的菜蕨、初花期的苣荬菜为二级蔬菜,不可生食,可盐渍和熟食;盛花期的苣荬菜,幼苗期、营养生长期、初花期和果期的刺苋属于三级蔬菜,不可生食、盐渍,可熟食;初果期(盛花期)的刺苋属于四级蔬菜,应避免食用或限量熟食。 相似文献
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The nitrate and nitrite contents of four kinds of vegetables (spinach, crown daisy, organic Chinese spinach and organic non-heading Chinese cabbage) in Taiwan were determined during storage at both refrigerated (5 ± 1°C) and ambient temperatures (22 ± 1°C) for 7 days. During storage at ambient temperature, nitrate levels in the vegetables dropped significantly from the third day while nitrite levels increased dramatically from the fourth day of storage. However, refrigerated storage did not lead to changes in nitrate and nitrite levels in the vegetables over 7 days. 相似文献
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目的 探索冰箱冷藏(4℃)条件下蔬菜中硝酸盐和亚硝酸盐含量随时间的变化,对冷藏食品的安全性进行评价.方法 分别采用重氮偶合分光光度法和麝香草酚分光光度法对生菜、菠菜、油麦菜及苦苣4种常用蔬菜在冷藏条件下其亚硝酸盐及硝酸盐的含量变化进行测定.结果 1~4d内,生菜、苦苣中的亚硝酸盐含量随着时间的延长逐渐增加;菠菜、油麦菜中亚硝酸盐含量分别在第2天和第3天达到最大,之后逐渐降低,而菠菜中亚硝酸盐含量在第4天又出现上升趋势.4种蔬菜中亚硝酸盐含量4d中最大值仅为0.419 4 mg/kg(生菜),均<4 mg/kg的限量值.苦苣和油麦菜中硝酸盐含量在1~4d内逐渐上升.菠菜中硝酸盐含量第2天达到418.48 mg/kg,之后又降低至20.83 mg/kg.生菜中硝酸盐含量在第3天达到最大值317.26 mg/kg,之后逐渐下降,但均在安全范围内(432 mg/kg).结论 在4℃下冷藏4d后,4种常见蔬菜均可安全食用.可见,冷藏能有效减缓亚硝酸盐和硝酸盐含量的升高. 相似文献
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The nitrate and nitrite content of leaf vegetables (Swiss chard, sea beet, spinach and cabbage), “inflorescence” vegetables (cauliflower) and fruit vegetables (eggplant and vegetable marrow) grown with organic fertilizers have been determined by a modified cadmium–Griess method. Samples were purchased from organic food stores as well as collected directly from an organic farm in Madrid (Spain). Nitrate levels were much higher in the leaf vegetables (especially Swiss chard species; average over the different samples and species of 2778.6 ± 1474.7 mg kg? 1) than in inflorescence or fruit products (mean values between 50.2 ± 52.6 and 183.9 ± 233.6 mg kg? 1). Following Swiss chard species, spinach (1349.8 ± 1045.5 mg kg? 1) showed the highest nitrate content, and nitrite was found above the limit of detection in some samples only (spinach, 4.6 ± 1.0 mg kg? 1; sea beet, 4.2 ± 0.7 mg kg? 1 and Swiss chard, 1.2 ± 0.4 mg kg? 1). Some vegetables (spinach, cabbage and eggplant) had lower nitrate content in the samples harvested in summer, showing the influence of climatic conditions on the nitrate levels in a plant. The samples taken directly from the organic farm, with the exception of eggplant, had higher or slightly higher average nitrate values than samples purchased in the organic food stores, ranging from 117 to 1077%. 相似文献
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David J Lyons George E Rayment Peter E Nobbs Leith E McCallum 《Journal of the science of food and agriculture》1994,64(3):279-281
Vegetables were collected near peak harvest from the main production regions in Queensland and were analysed for residues of nitrate and nitrite. A small sample of hydroponic produce was also included in the survey. Nitrite-N from 1 to 4 mg kg-1 was found only in dwarf beans and in lettuces. Levels of nitrate in potatoes, cabbages and beets were higher than those reported in other surveys and exceeded threshold limits set in one other country. The median nitrate-N concentration measured in hydroponic lettuce (465 mg kg-1 nitrate-N) was more than twice the median concentration for field-grown lettuce. Poor correlation between total N and nitrate in vegetables raises doubts about the use of total N alone as an indicator of N status. 相似文献