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1.
研究重庆4 个农贸市场市售3大类19 种蔬菜73 个样品中硝酸盐含量及重庆市13 个主要蔬菜基地土壤和蔬菜的硝酸盐、亚硝酸盐含量及相关性。结果表明,重庆市售蔬菜不同种类及同种蔬菜不同部位的硝酸盐含量差异显著。大小顺序为叶菜类(X =1 619.73 mg/kg)>茄果类(X =1 327.67 mg/kg)>葱蒜类(X =
1 078.39 mg/kg);莴苣叶(X=1 567.91 mg/kg)>莴苣茎(X=1 871.62 mg/kg)。叶菜类全部超过了一级标准,污染指数高达9.09,污染程度最为严重;茄果类和葱蒜类超过一级标准的样本占81.3%和87.5%,污染指数分别高达8.85和6.56。重庆市13 个主要蔬菜基地不同蔬菜以及同种蔬菜不同部位的硝酸盐含量差异也显著,大小顺序为萝卜叶(X=745.97 mg/kg)>莴苣茎(X=730.88 mg/kg)>莴苣叶(X=693.32 mg/kg)>白菜(X=617.63 mg/kg)>萝卜根(X=575.74 mg/kg)。土壤中NO3--N含量差异也显著,大小顺序为种植莴苣的土壤(X=75.24 mg/kg)>种植白菜的土壤(X=47.05 mg/kg)>种植萝卜的土壤(X=33.42 mg/kg)。蔬菜可食部分的硝酸盐与土壤中的NO3--N含量呈极显著正相关关系,线性方程y=407.872+4.796x。供试重庆市13 个主要蔬菜基地土壤及蔬菜可食部分的NO2--N含量均较低且差异不显著,蔬菜中的亚硝酸盐含量和土壤中的NO2--N含量也无显著相关性。  相似文献   

2.
市售新鲜蔬菜硝酸盐含量测定及降低措施   总被引:3,自引:1,他引:2  
对六盘水市中心区几种市售新鲜蔬菜随机抽取,测定硝酸盐含量.结果表明:蔬菜硝酸盐含量超标率达72.7%,叶菜类、根菜类、茎菜类、瓜类、豆类都有不同程度的超标.不同的蔬菜种类硝酸盐含量差异大,其中叶菜类蔬菜普遍高于其他蔬菜种类.针对六盘水市售蔬菜硝酸盐污染状况,建议在生产、食用环节采取相应措施,降低蔬菜硝酸盐含量,保障市民身体健康.  相似文献   

3.
随机抽取深圳市市售的7类蔬菜86批次样品,进行硝酸盐含量检测并分析。结果表明,在不同类型的蔬菜中硝酸盐的含量差异较大,总体而言,叶菜类蔬菜的硝酸盐含量最高,其余依次为根菜类、鳞茎类、瓜类、豆类、茄果类与食用菌类。在所调查的86批次样品中,硝酸盐含量低于432 mg/kg的蔬菜所占比为65.1%,高于1 440 mg/kg的蔬菜所占比为16.3%。  相似文献   

4.
北京市春季蔬菜硝酸盐含量测定及居民暴露量评估   总被引:7,自引:0,他引:7       下载免费PDF全文
为了解北京市春季蔬菜中硝酸盐污染及居民硝酸盐暴露情况,于2006年3-5月从北京市16个菜市场采集应季蔬菜7大类26个品种341份样品,用国标法(GB/T5009.33—2003)分析蔬菜中的硝酸盐含量。随机抽取北京市15岁以上常住居民152户428人,以记账法对居民日常蔬菜摄入量进行调查,结合蔬菜硝酸盐含量的检测结果,进行居民蔬菜硝酸盐暴露量评估。叶菜类硝酸盐含量最高(3156.94±1425.62mg/kg),茄果类的含量最低(172.36±148.08mg/kg),硝酸盐含量依次为叶菜类>根茎类>葱蒜类>瓜类>豆菜类>花菜类>茄果类,但同一类蔬菜不同品种的硝酸盐的含量差别较大;同一品种的蔬菜中硝酸盐含量差别也很大。居民每日通过蔬菜摄入的硝酸盐量为328.21mg(以中位数计),比WHO/FAO的ADI值(300mg/d)高9.4%。北京市春季蔬菜的硝酸盐污染较严重,居民仅由蔬菜摄入的硝酸盐量已经高于ADI值,因此需要加强监督管理,以保护居民健康。  相似文献   

5.
本文报道了武汉市四类食品(粮食、蔬菜、鱼肉制品、水)中亚硝酸盐、硝酸盐含量的调查结果。结果表明,四类食品中都含有亚硝酸盐,硝酸盐。在四类食品中,鱼肉制品中亚硝酸盐含量均值(5.75mg/kg)高于其它食品,蔬菜中硝酸盐含量均值(1298.21mg/kg)高于其它食品。肉制品又以香肠中亚硝酸盐、硝酸盐含量的均值(7.79mg/kg、653.44mg/kg)为最高,硝酸盐残留量超标率达33%。蔬菜类食品中,不同的蔬菜,亚硝酸盐、硝酸盐含量不同。亚硝酸盐以黑白菜为高(7.02mg/kg)硝酸盐以菠菜为最高(3874.50mg/kg),其次是芹菜(3368.25mg/kg)藕中亚硝酸盐、硝酸盐含量(0.51mg/kg、27.56mg/kg)均低。根据调查结果,对60公斤体重成人每日亚硝酸盐、硝酸盐的摄入量作了初步估计,亚硝酸盐摄入量为3.37mg,硝酸盐摄入量为671.19mg。硝酸盐摄入量超过了每日允许摄入量(219mg/60kg、b.w)。  相似文献   

6.
邱贺媛  曾宪锋 《食品科学》2005,26(8):324-326
测定了荠菜、泥胡菜和多头苦荬菜等3种野菜不同发育阶段叶中的硝酸盐、亚硝酸盐和维生素C的含量。参考蔬菜中硝酸盐含量分级评价标准,参考我国制定的无公害蔬菜亚硝酸盐含量限量标准(以NaNO2计≤4.0mg/kg),考虑到各种野菜的维生素C的含量,对这3种野菜评价如下:泥胡菜和多头苦荬菜的各个时期的叶,硝酸盐含量低于轻度污染水平444mg/kg,亚硝酸盐含量低于我国制定的无公害蔬菜亚硝酸盐含量的限量标准,所以,它们属于一级野菜,可以安全食用;果期荠菜的叶,硝酸盐含量低于807mg/kg,属于中度污染水平,亚硝酸盐含量低于我国制定的无公害蔬菜亚硝酸盐含量的限量标准,属二级蔬菜范围,不宜生食,煮熟或盐渍可安全食用:荠菜的期于各期叶的硝酸盐含量高于807mg/kg而低于1268mg/kg,亚硝酸盐含量低于我国制定的无公害蔬菜亚硝酸盐含量的限量标准,属于三级蔬菜,不可生食和盐渍,可熟食。  相似文献   

7.
厦门市售蔬菜重金属、硝酸盐和亚硝酸盐污染研究及评价   总被引:8,自引:0,他引:8  
为了解厦门市蔬菜中有害重金属、硝酸盐和亚硝酸盐的污染情况,于2004年8月至2005年12月从厦门市各超市、农贸市场、蔬菜批发市场和蔬菜产地上采集46个品种532份蔬菜样品,用国标法(GB/T5009.11-17-1996、GB/T5009.33-2003)分别分析蔬菜中的重金属、硝酸盐和亚硝酸盐的含量。结果表明,检测样品中Pb、Cd、As、Hg、硝酸盐和亚硝酸盐的平均值分别为0.0099、0.083、0.056、0.003、1090.3、0.59mg/kg;根据国家标准1-2,仅部分品种如菠菜、甘蓝、花菜、萝卜的铅超标,有潜在污染风险;大部分蔬菜中砷、汞、镉三种重金属的含量都较低,潜在的污染风险不大。硝酸盐污染程度严重的占36.5%;中、重度污染的占20.2%;轻度的占43.3%,硝酸盐含量依次为嫩茎叶菜类>根茎类>花菜类>瓜菜类>鲜豆菜>茄果类>水生蔬菜类,各样品间含量差别较大;而蔬菜中亚硝酸盐含量相对较低。  相似文献   

8.
不同贮存条件下四种新鲜蔬菜亚硝酸盐含量变化探究   总被引:1,自引:0,他引:1  
为更加安全、合理储藏与食用蔬菜,本文选取叶菜类小白菜、茎菜类土豆、果菜类黄瓜、根茎类白萝卜四种蔬菜,采用盐酸萘乙二胺法探究时间、温度、储存方式对亚硝酸盐含量变化的影响。结果表明,常温(25℃)保存,4种蔬菜的亚硝酸盐含量均高于低温(4℃)保存。常温、敞开状态下,亚硝酸盐含量变化最大,敞开时含量大于密封时,小白菜在25℃下情况相反。同时,小白菜在常温下出现含量超标情况,其他蔬菜均小于4 mg/kg,符合国家标准。总体上,新鲜蔬菜(0 d)的亚硝酸盐含量相对较低,低温且密封更有利于蔬菜保存,建议优先食用叶菜类蔬菜。  相似文献   

9.
目的:测定不同蔬菜品种的木聚糖含量,分析不同蔬菜品种木聚糖含量的差异,为蔬菜高值化加工及人们对蔬菜木聚糖膳食纤维精准补充提供科学依据。方法:以南方常见41个蔬菜品种为研究对象,采用稀酸水解、高效液相色谱法测定蔬菜木聚糖的含量。结果:不同蔬菜品种木聚糖的含量差异显著,41种蔬菜品种中,每100g新鲜原料木聚糖含量排名前3的分别是豌豆(2. 37g)、蚕豆(2. 19g)、甜玉米(1. 86g),其他蔬菜品种木聚糖含量均小于1. 6g。根据食用器官蔬菜木聚糖含量平均值排序:花菜类果菜类茎菜类食用菌类根菜类叶菜类。结论:补充蔬菜木聚糖膳食纤维,优选果菜类中的豆类。  相似文献   

10.
北京市蔬菜硝酸盐和亚硝酸盐污染状况评价   总被引:14,自引:2,他引:14       下载免费PDF全文
为了解北京市蔬菜中硝酸盐和亚硝酸盐的污染情况 ,于 2 0 0 3年 4月~ 8月从北京 15个菜市场采集应季蔬菜样品 ,共 4 0个品种 4 44份样品 ,用国标法 (GB T 5 0 0 9 33— 2 0 0 3)分析蔬菜中的硝酸盐和亚硝酸盐的含量。结果显示 :检测样品中 ,污染程度严重的占 33 1% ;中、重度污染的占2 3 6 % ;轻度的占 4 3 2 % ;硝酸盐的含量依次为绿叶菜类 >白菜类 >根茎类 >瓜茄类 >葱蒜类 >豆类 >果类 >水生植物类 ,但同一类蔬菜不同品种的硝酸盐的含量差别较大 ,从几倍到几十倍 ;同一品种的蔬菜中硝酸盐含量差别也很大 ,可能与产地、生长条件不同有关。蔬菜中亚硝酸盐含量相对较低 ,其含量与蔬菜的新鲜程度有关。研究结果提示需要制定限量标准 ,加强监督管理  相似文献   

11.
A scientific basis for the evaluation of the risk to public health arising from excessive dietary intake of nitrate in Korea is provided. The nitrate () and nitrite () contents of various vegetables (Chinese cabbage, radish, lettuce, spinach, soybean sprouts, onion, pumpkin, green onion, cucumber, potato, carrot, garlic, green pepper, cabbage and Allium tuberosum Roth known as Crown daisy) are reported. Six hundred samples of 15 vegetables cultivated during different seasons were analysed for nitrate and nitrite by ion chromatography and ultraviolet spectrophotometry, respectively. No significant variance in nitrate levels was found for most vegetables cultivated during the summer and winter harvests. The mean nitrates level was higher in A. tuberosum Roth (5150 mg kg(-1)) and spinach (4259 mg kg(-1)), intermediate in radish (1878 mg kg(-1)) and Chinese cabbage (1740 mg kg(-1)), and lower in onion (23 mg kg(-1)), soybean sprouts (56 mg kg(-1)) and green pepper (76 mg kg(-1)) compared with those in other vegetables. The average nitrite contents in various vegetables were about 0.6 mg kg(-1), and the values were not significantly different among most vegetables. It was observed that nitrate contents in vegetables varied depending on the type of vegetables and were similar to those in vegetables grown in other countries. From the results of our studies and other information from foreign sources, it can be concluded that it is not necessary to establish limits of nitrates contents of vegetables cultivated in Korea due to the co-presence of beneficial elements such as ascorbic acid and alpha-tocopherol which are known to inhibit the formation of nitrosamine.  相似文献   

12.
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   

13.
To evaluate nitrate and nitrite contents in cabbage and potatoes, the most consumed vegetables in Croatia, and to examine if war-time operations in Croatia affected nitrate and nitrite levels in vegetables, potatoes and cabbage cultivated in the war region (East Slavonia) and out of war regions were analyzed. Data showed that nitrate contents were higher in the samples from the war region (32% and 24% in potatoes and cabbage, respectively) but differences were not statistically significant. The nitrate levels found in potato samples (196 mg NaNO3/kg fresh weight (FW) and cabbage samples (911 mg NaNO3/kg FW) were comparable with levels reported for other countries. The nitrite contents in potatoes (321 μg NaNO2/kg FW) and cabbage (173 μg NaNO2/kg FW) were lower than the contents reported for most other countries. Further examinations of nitrate and nitrite concentrations in vegetables in Croatia as well as examinations of the influence of war-time operations on accumulation of these toxic contaminants are necessary.  相似文献   

14.
High dietary nitrate and nitrite intake may increase the risk of gastro-intestinal cancers due to the in vivo formation of carcinogenic chemicals known as N-nitroso compounds. Water and leafy vegetables are natural sources of dietary nitrate, whereas cured meats are the major sources of dietary nitrite. This paper describes a simple and fast analytical method for determining nitrate and nitrite contents in vegetables and meat, using reversed-phase HPLC-UV. The linearity R2 value was >0.998 for the anions. The limits of quantification for nitrite and nitrate were 5.0 and 2.5 mg/kg, respectively. This method is applicable for both leafy vegetable and meat samples. A range of vegetables was tested, which contained <23 mg/kg nitrite, but as much as 5000 mg/kg of nitrate. In cured and fresh meat samples, nitrate content ranged from 3.7 to 139.5 mg/kg, and nitrite content ranged from 3.7 to 86.7 mg/kg. These were below the regulatory limits set by food standards Australia and New Zealand (FSANZ). Based on the average consumption of these vegetables and cured meat in Australia, the estimated dietary intake for nitrate and nitrite for Australians were 267 and 5.3 mg/adult/day, respectively.  相似文献   

15.
A novel ion chromatographic method to detect nitrates in vegetables was developed, and the nitrate contents in green salad (a mixture of endive and prickly lettuce), lettuce, chicory, rocket and spinach were determined from Italian markets in 1996 -2002. These leaf vegetables were included because they are currently supposed to provide most of the nitrate intake in the typical Italian diet. The highest content of nitrate was detected in chicory (6250 mg kg -1 ) and rocket (6120 mg kg -1 ), which are consumed in large quantities in some regions of Italy. Green salad and lettuce contained less nitrate (highest values = 4200 and 3300 mg kg -1 , respectively), but because they are consumed more generally, they provided 60% of the total intake of nitrates. Only a few samples were above the legal limits, with seasonal variation. A significantly higher nitrate content was found in organically grown green salad and rocket than in those conventionally produced. These data indicate that the average intake of nitrates from leafy vegetables is below the acceptable daily intake, i.e. 3.7 mg nitrate ion kg -1 body weight day -1 , but the total intake should be monitored to protect groups at risk, such as children and vegetarians.  相似文献   

16.
了解甘肃省市售浆水中亚硝酸盐的含量。方法 对GB 5009.33—2010《食品中亚硝酸盐与硝酸盐的测定》方法做了改进,省略了沉淀蛋白质的步骤;并按照改进的方法测定了采集于2013年4月至8月的62份浆水样品中亚硝酸盐的含量。结果 62份样品中亚硝酸盐含量均低于2 mg/kg,平均亚硝酸盐含量为0.64 mg/kg;含菜浆水亚硝酸盐含量高于不含菜浆水。结论 依据GB 2762—2012《食品中污染物限量》中规定的蔬菜及其制品、腌渍发酵蔬菜中亚硝酸盐最大量为20 mg/kg,62份样品中亚硝酸盐含量均未超标。  相似文献   

17.
Nitrates form part of the essential chemistry of soils and plants. Thus, plant roots are able to absorb nitrate directly from the soil. It has been discovered that human nitrate intake is mainly from vegetables. Vegetables play an important role in human nutrition since they are an outstanding source for vitamins, minerals, and biologically active compounds. In risk assessment of nitrate contents, this study reports the nitrate levels of 8 commonly consumed fruits and vegetables grown in Fiji, tomato (Lycopersicon esculentum), eggplant (Solanum melongena), capsicum (Capsicum annuum var. grossum), breadfruit (Artocarpus altilis), long bean (Vigna sesquipedalis), jackfruit (A. heterophyllus), pumpkin (Cucurbita pepo), and cucumber (Cucumis sativus). The effects of different types of cooking methods, baking, boiling, and frying, have also been studied. The validated flow injection analysis technique has been used to quantify the nitrate-N levels in the chosen products following nitrate extraction using the activated carbon technique. The mean values of nitrate levels in fresh products ranged from 25.83 to 281.02 mg NO(3) (-) kg(-1) . The study shows that boiling reduced nitrate contents by 65.37% to 25.25%. The frying in soy bean oil elevated nitrate contents from 354.79% to 86.69%, but after baking, nitrate contents remained almost constant with slight increasing trend in the case of tomato (19.97%). The nitrate levels published in the literature for the same types of fruits and vegetables studied have also been reviewed and compared. The average nitrate-N values were comparable or lower than overseas data, but did not present unpredictably high values, that is, they were below the risk level.  相似文献   

18.
目的 对当地常见的富锶蔬菜进行复核和人工种植,研究品种及环境因素对蔬菜中锶含量的影响规律.方法 针对前期调查中富锶植物的分布规律,对含锶量较高、生长迅速、便于多次采样的绿叶蔬菜进行大棚种植,并用富锶水浇灌,采样后测定锶含量.结果 所有检测的35种共229份蔬菜样品中,有9种蔬菜样品的平均含锶量超过1.0 mg/kg,与...  相似文献   

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