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目的建立微波消解-原子吸收法测定食品中钙含量的方法。方法采用微波消解法对样品进行前处理,在检测样品中加入氯化镧(8 g/L)屏蔽剂,用火焰原子吸收法进行检测。比较经消解后样品中不同的硝酸浓度对钙含量测定结果的影响,探究微波消解法测定食品中钙含量时结果偏低的原因。结果经微波消解后,样品中的硝酸含量大于0.5%时,会导致钙含量的检测结果偏低。经湿法消解处理的样品,其加标回收率在97.2%~106.0%之间,经微波消解法处理的样品,其加标回收率在96.8%~104.0%之间。将采用上述两种消解方法处理的样品的钙含量检测结果进行比较,测定值间的相对误差为1.64%~3.08%,在可接受范围内。结论微波消解-原子吸收法可以用于食品中钙含量的检测。 相似文献
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用硝酸和高氯酸即湿式消化法处理牛奶样品,采用火焰原子吸收分光光度法测定并以硝酸镧为释放剂测定牛奶钙锌含量。探讨不同条件对牛奶中钙,锌含量测定的影响,确定最佳测定条件。本方法一定浓度共存离子不产生干扰,加标回收率在97%~99%之间,且测定方法方便,快速。 相似文献
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将饲料样品烘干、粉碎和过筛,在加热条件下用浓硝酸消解样品,使绝大部分样品组分(95%以上)进入溶液,再加入乳化剂聚乙二醇辛基苯基醚(OP),将其悬浮在1.5 g/L 5 mL琼脂溶液中制成非完全消化悬浮液,以氧化镧(La2O3)作为释放剂以消除化学干扰。用火焰原子吸收法光谱法成功测定了饲料中的镁、锌、铜微量元素,测定结果的相对标准偏差小于3.0%。试验结果与灰化法一致,此方法简便、快速、准确。 相似文献
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目的:建立茶油无机元素的测定方法,为制订茶油有害金属元素限量标准提供参考,同时为其健康食用和规范化栽培基地的选择提供依据。方法:用火焰原子吸收光谱法(FAAS)测定Ca、Fe、Mg、Cu、Zn和K的含量,用石墨炉原子吸收光谱法(GFAAS)测定Pb、Cd和Cr的含量。结果:12份样品中K、Ca、Mg和Fe的含量较高,有害金属元素Pb、Cd和Cr在川雅12、川雅20、川雅21中均未检测出,在其余样品中含量也较低。FAAS法测定Ca、Fe、Mg、Cu、Zn和K的回收率为99.84%~102.55%,RSD为0.55%~2.05%;GFAAS法测定Pb、Cd和Cr的回收率为99.75%~101.85%,RSD为1.87%~3.45%;各元素的相关系数为0.9990~0.9999。结论:该方法操作简便,准确性高,结果可靠,可作为茶油无机元素的定量检测方法。 相似文献
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用硝酸和高氯酸即湿式消化法处理牛奶样品,采用火焰原子吸收分光光度法测定并以硝酸镧为释放剂测定牛奶钙锌含量.探讨不同条件对牛奶中钙,锌含量测定的影响,确定最佳测定条件.本方法一定浓度共存离子不产生干扰,加标回收率在97%~99%之间,且测定方法方便,快速. 相似文献
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目的以重金属铅(Pb)为测定对象,建立一种快速、高效、简便的检测方法测定食品中痕量的重金属,即流动注射(FI)空气混合法在线预富集与火焰原子吸收光谱法(FAAS)联用测定食品中痕量的重金属。方法样品溶液、络合剂和空气分别通过3条管子同时进样,金属离子和络合剂在线混合反应,其络合物流经编结反应器(KR)并吸附在其内壁,通入一段空气流,防止前后溶液混和并提高富集效果,用乙醇作为洗脱剂洗脱后送入火焰原子吸收光谱仪进行测定。结果与传统的流动注射与火焰原子吸收光谱法联用系统相比,此方法减少了样品的富集时间,达到了更好地吸附效果,提高了检测方法的灵敏度,线性相关系数良好(R0.9983),检出限低,精密度好,加标回收率在97.3%~100.5%之间。结论该方法应用于沙丁鱼中重金属铅的测定,结果满意。 相似文献
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Infant formula developed by manufacturers requires a rigorous control of composition, particularly those elements added routinely in an attempt to mimic the mineral composition of human milk. A total of 97 different types of powdered infant formulae (preterm, adapted starter, adapted follow-up, toddler, specialised and soy-based formulae) commercially available in Spain were studied. It is noteworthy great differences in mineral (Ca, P, Mg) and trace element (Zn, Fe, Cu, Mn) contents found between analysed and listed in label information. The development of a fast, simple and direct slurry method for the determination of these essential micronutrients in infant formula by inductively coupled plasma optical emission spectrometry (ICP OES) and flame atomic absorption spectrometry (FAAS) was performed in order to help in quality control tasks. Infant formula samples were solubilised using different amounts of several different solvents. An addition of 250 μL of a solution 10% tetramethylammonium hydroxide and 25% ammonium hydroxide were required for the accurate quantification of Ca and P, Mg, Zn, Fe, Cu and Mn, respectively. The standard reference material 1549 non-fat milk powder was solubilised to compare the validity of assayed methodology following slurry nebulisation and traditional microwave-assisted acid digestion method. Good agreement of the analytical results by both ICP OES and FAAS, with the certified values was obtained. Method performance parameters (accuracy, precision and methodological detection limits) were determined for studied elements to check the quality and usefulness of the optimised slurry method. The analytical procedure was applied successfully to the analysis of a representative group of infant formulae. Levels of analysed elements were graphically represented, showing an acceptable comparability between slurry and acid-mineralisation method set by linear correlation coefficients and slopes close to the unit. The described simple and slurry method is appropriate, as an attractive alternative, for routine control analysis of added essential elements in infant formulae regardless of predominant protein type used in manufacture. 相似文献
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将海产品样品烘干、粉碎、过筛,在加热条件下用浓硝酸消解样品,使绝大部分样品组分(95% 以上)被分解或转入溶液中,再加入乳化剂OP,最后将其悬浮在琼脂溶液中制成非完全消化悬浮液,用La2O3 作为释放剂以消除测钙时的化学干扰。用原子吸收光谱法成功测定了虾、螃蟹和鲳鱼中的钙、锌、铜微量元素,测定结果的相对标准偏差小于等于3.0%。从而证明采用非完全消化- 悬浮液进样- 火焰原子吸收光谱法测定海产品中微量元素是可行的。此方法简便、快速、准确。 相似文献
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为了探索奶粉产地溯源的可靠方法,以3个不同产区的12种奶粉为研究对象,分别用电感耦合等离子体发射光谱法(ICP)测定了样品中的Ca、K、Mg、Na、Al、Fe、Sr共7种元素的含量,用电感耦合等离子体质谱法(ICP-MS)测定了样品中的Li、Cr、Mn、Co、Ni、Cu、Zn、Se、Ba、Pb、Sc、Y、La、Ce、Nd共15种元素的含量,用分光光度法测定了P元素的含量,采用SPSS统计分析对上述23种元素的含量分别进行了方差分析、主成分分析和聚类分析。结果表明:不同地区的奶粉样品中元素含量有其各自的特征。主成分分析和聚类分析使奶粉样品分成不同的类别,其类别与品种及来源地基本一致,聚类的整体正确率为91.67%。 相似文献
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采用微波消解-火焰原子吸收法测定大西洋鲑肌肉中9种矿物质元素的含量,建立微波三阶段梯度升温消解技术,确定最佳消解条件和原子吸收分光光度计工作条件。大西洋鲑肌肉中Ca、Fe、Mn、Zn、Mg、Cu、Cr、Cd、Pb的含量分别为292.6,1.8,1.6,2.9,149.2,0.005 3,0.004 4,0.003 7,0.011 5μg/g。结果表明:大西洋鲑肌肉中含有多种对人体有重要生理功能的矿物质和微量元素,比例恰当,具有较高的营养价值。其中Cd、Pb、Cr、Cu等重金属含量均远远低于在中国国标产品安全卫生指标,可以安全食用。 相似文献
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Kelber Miranda Alan Lima Vieira Marcos André Bechlin Felipe Manfroi Fortunato Alex Virgilio Edilene Cristina Ferreira José Anchieta Gomes Neto 《Food Analytical Methods》2016,9(7):1887-1894
Establishing fast, simple, low-cost, and efficient sample preparation procedures to determine elements in foodstuffs is a relevant aspect for nutritional and health purposes. For this reason, the recently proposed closed-vessel conductively heated digestion system (CHDS) was evaluated for the digestion of milk powder, chocolate powder, and soluble coffee samples aiming for Ca, Cu, Fe, K, Mg, Mn, Na, and Zn determinations by high-resolution continuum source flame atomic absorption spectrometry (HR-CS FAAS) and Cd, Mo, and Se determinations by inductively coupled plasma mass spectrometry with tandem configuration (ICP-MS/MS). The accuracy was evaluated by analyzing two milk certified reference materials digested by the CHDS and a microwave oven for comparison. When using the CHDS, recoveries for the analytes varied from 91 to 104 %. For microwave digestions, recoveries within the 94–109 % intervals were obtained. The method was then applied to the samples. For comparative purposes, the analytes were also determined in the samples after microwave digestion, and the results between the two digestion systems showed no differences based on a paired t test at a 95 % confidence level. Similar analytical blanks were obtained because quartz digestion tubes were used in both digestion systems. The CHDS with quartz tubes is an interesting alternative for laboratories dedicated to large-scale routine analysis because volatile elements usually found in very low concentrations in food samples such as Cd and Se can also be determined. 相似文献
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目的建立自动标准加入法测定乳粉、乳饮料和果汁中钠含量的方法。方法采用自动标准加入法对全脂奶粉、脱脂奶粉、浓缩乳清粉、婴幼儿配方奶粉以及市场上各类果汁饮料及乳饮料进行钠含量的测定,研究样品中钠离子的提取方式和滴定剂浓度对检测结果的影响,并将测定结果与火焰原子发射光谱法进行对比。结果自动标准加入法用于乳粉、浓缩乳清粉、果汁饮料及乳饮料中钠含量的测定结果重复性好,相对标准偏差均小于5%;而且与火焰原子发射光谱法的测定结果之间无显著性差异,两者之间的相对偏差小于5%。结论自动标准加入法重复性好、准确度高,可用于食品与饮料中钠含量的检测。 相似文献
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采用微波消解法处理样品,用硝酸-双氧水(体积比6∶1)混合溶液作为消解剂进行微波消解,火焰原子吸收光谱法测定了市售3种珍珠粉中锌、钠、镁、铁、钙、铜、锰、锶等8种金属元素含量。8种元素检出限(3S/N)在0.000 6~0.024 8 mg/L,回收率95%~105%,相对标准偏差(n=10)<5%。试验结果表明:3种珍珠粉样品中8种金属含量的数值变化趋势较为一致,其中钙含量最高,含量均达34.15%以上,锰、锶、铁、钠的含量也较为丰富,均在94.74μg/g以上,而锌、镁、铜含量相对较少,均少于11.78μg/g。从珍珠粉的主要成分金属元素钙的含量测定结果可以推断出3种珍珠粉的品质有所差别,钙含量低的质量相对差。 相似文献
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微波消解-释放剂辅助火焰原子吸收分光光度法测定蛋白质粉中的钙 总被引:1,自引:0,他引:1
建立采用微波消解-释放剂辅助火焰原子吸收分光光度法(flame atomic absorption spectrophotometry,FAAS)测定蛋白质粉中钙的方法。探讨消解体系、消解压力、消解时间以及增压方式对消解结果的影响,选择硝酸镧为释放剂,研究待测样品中硝酸镧的质量浓度对钙元素释放的影响。结果表明,在最佳的实验条件下,钙的线性范围为1~20μg/mL,检出限为0.15μg/mL,测定蛋白质粉中钙的质量分数为0.46%,精密度为1.63%,加标平均回收率为96.8%,相对标准偏差为2.34%。该方法线性范围宽、相关性好,准确度和精密度高,具有较高的实用价值。 相似文献
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目的优化火焰原子吸收法测定乳粉中锰的分析方法。方法对火焰原子吸收分光光度计仪器的燃烧器高度、助燃比等仪器条件进行优化,确定最佳实验条件。结果最佳仪器条件:灯电流7.5 mA;狭缝宽度:0.2 nm;燃烧器高度10 mm;燃气流量:2.4 L/min,助燃气流量:15.0 L/min。在最佳仪器条件下乳粉中的锰0~3 mg/L范围内线性关系良好,相关系数在0.9995以上,检出限为0.0099 mg/kg、回收率为93.6%~99.5%,精密度为0.66%~3.49%。结论本方法具有灵敏度高、准确度高、精密度好等优点,适用于乳粉中锰的含量测定。 相似文献