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研究了利用高效液相色谱法快速测定小米中添加的柠檬黄色素的方法.通过温水处理提取小米中的水溶性色素,采用色谱条件在254 nm的波长下,采用等度洗脱法,样品处理及检测简便快速.方法标准偏差0.0024,添加标准回收率93.3%~96.3%. 相似文献
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Padmaja R. Jonnalagadda Pratima Rao Ramesh V. Bhat & A. Nadamuni Naidu 《International Journal of Food Science & Technology》2004,39(2):125-131
The type and extent of colours added to ready‐to‐eat (RTE) foods prepared in the non‐industrial sector of India was investigated. Of the 545 RTE foods analysed, 90% contained permitted colours, 2% contained a combination of permitted and non‐permitted colours and 8% contained only non‐permitted colours. However in RTE foods with permitted colours, 73% exceeded 100 ppm, as prescribed by the Prevention of Food Adulteration Act of India, and 27% were within the prescribed levels. Among the permitted colours, tartrazine was the most widely used colour followed by sunset yellow. The maximum concentration of colours was detected in sweet meats (18 767 ppm), non‐alcoholic beverages (9450 ppm), miscellaneous foods (6106 ppm) and hard‐boiled sugar confectioneries (3811 ppm). Among the non‐permitted colours found, rhodamine was most commonly used. Some of the foods, such as savouries and miscellaneous foods like sugar coated aniseed and almond milk, are not supposed to contain colours as per the Prevention of Food Adulteration Act, but were found to contain colours. 相似文献
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目的:本实验通过对国标中合成色素检测前处理方法的改进,考察了吸附解吸装置、洗脱剂中氨水比例、聚酰胺粉用量、旋转蒸发温度对实验结果的影响,建立了测定果汁饮料中柠檬黄、日落黄的HPLC检测方法.方法:样品经聚酰胺粉吸附,甲醇—甲酸溶液除去天然色素,乙醇—氨水—水混合溶液(5:4:1)洗脱,70℃旋干溶液,复溶后经C18液相色谱柱分离,甲醇-0.02mol/L乙酸铵溶液(pH=4)梯度洗脱,紫外检测器检测.结果:柠檬黄的检出限为0.2mg/kg,日落黄的检出限为0.3mg/kg.柠檬黄和日落黄的回收率均>99.0%.结论:该方法稳定性好、回收率高、适用范围广,可用作复杂基质中多种合成色素的同时检测. 相似文献
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《分离科学与技术》2012,47(1):75-83
Abstract Empirical equations with correlation coefficients greater than 0.9 for the solvent extraction of GeCl4, GeBr4, acetylacetone, trifluoroacetylacetone, thenoyltrifluoroacetone, 1-nitropropane, bis-thenoyltrifluoroacetone zinc(II), and several dicarboxylic acids in various solvents are presented. 相似文献
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该文报道利用高效液相色谱法快速测定小米中添加柠檬黄色素方法。首先采用温水提取小米中水溶性色素,然后以乙酸铵+甲醇(80+20)固定配比为流动相,流速为1 ml/min。在254nm波长下检测。与国标法相比,该法简便快速,方法标准偏差0.0024,添加标准回收率93.3%- 96.3%,可用于大多数粮食中合成色素测定。 相似文献
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Adsorption of tartrazine and methylene blue from aqueous solution onto activated carbon has been investigated. Experimental datas obtained from dye adsorption have been studied by five two-parameter (Langmuir, Freundlich, Dubinin-Radushkevich, Temkin, and Frumkin), five three-parameter (Redlich-Peterson, Sips, Toth, Radke-Prausnitz, Koble-Corrigan) isotherm models. In this study, eight nonlinear error functions (sum squares errors, hybrid fractional error function, Marquardt's percent standard deviation, average relative error, sum of absolute error, the coefficient of determination, nonlinear chi-square test, and standard deviation of relative errors) were examined for isotherm equations. In order to clarify the adsorption kinetics fit of pseudo-first order and pseudo-second order kinetic models were used. The best fitting isotherm model was the Radke-Prausnitz and kinetics model was pseudo-second order for two dyes. Adsorption experiment showed that the maximum capacity of activated carbon's for methylene blue and tartrazine were 28.571 and 18.182 mg.g?1, respectively. 相似文献
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TiO2 nanoparticles on calcined sewage sludge (TiO2/sludge) were prepared by the sol-gel method and were fully characterized. The photocatalytic efficiency of TiO2/sludge was evaluated by tartrazine dye degradation by halide lamp. TiO2/sludge exhibited a high photocatalytic oxidation efficiency (more than 90%) of tartrazine compared with naked TiO2 (less than 20%) due to the synergy effect of sewage sludge. The optimization of experimental conditions was 0.5 g/l TiO2/Sludge, pH 8 with 50 mg/l tartrazine dye. The addition of sewage sludge to TiO2 improves the efficiency of dye mineralization. The prepared catalyst showed easier separation and effective reuse. 相似文献
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采用液相剥离法制备石墨烯纳米片悬浮液,将其直接滴涂于玻碳电极表面,制备石墨烯修饰电极,再采用电沉积法制得聚嘧啶/石墨烯复合膜修饰电极。采用扫描电子显微镜对该修饰电极的表面形貌进行表征;采用循环伏安法和方波伏安法探究日落黄和酒石黄在该修饰电极上的电化学行为。结果表明,该复合膜修饰电极对两种合成色素均表现出良好的电催化性能。在优化实验条件下,日落黄和酒石黄同时被检测,线性检测范围分别为0.002~2?mol/L和0.003~6?mol/L,检测限分别为0.5 nmol/L和0.9 nmol/L。该方法可用于食品中日落黄和酒石黄的同时测定。 相似文献
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