饮料中日落黄含量测定的不确定度评定

目的对高效液相色谱法测定饮料中日落黄含量进行不确定度评定。方法分析日落黄含量测定过程中的样品称量等各种不确定因素,分析实验过程中各种不确定度的来源,计算合成不确定度和扩展不确定度。结果当日落黄含量为32 mg/kg时,其扩展不确定度为2.8 mg/kg(k=2)。由各不确定度分量的计算结果可知,日落黄标准溶液的配制过程对实验结果的不确定度影响最大。结论通过对测定过程的不确定度评定,可以把握不确定度的主要来源,为饮料中日落黄含量的测定提供理论依据,提高测定的精准度。     

Determination of sunset yellow (E110) in foodstuffs and pharmaceuticals after separation and preconcentration via solid‐phase extraction method

The two novel preconcentration and separation methods based on adsorption onto Amberlite XAD‐1180 and Amberlite XAD‐16 polymeric resins for spectrophotometric determination of sunset yellow dye were developed. The parameters, affecting the quantitative recovery, including pH, sample and eluent flow rates, eluent type, sample volume, were investigated and optimised. The interference effects of some cations, anions and widely used dye were also studied. At the optimum conditions, detection limits of the methods were found as 2.0 and 1.6 μg L^?1 for Amberlite XAD‐1180 and Amberlite XAD‐16 resins, respectively. Linear dynamic ranges of the methods were obtained in the range of 0.2–50.0 and 0.2–20.0 μg mL^?1 for Amberlite XAD‐1180 and Amberlite XAD‐16 resins, respectively. The relative standard deviations were below than 7% and 5% for Amberlite XAD‐1180 and Amberlite XAD‐16 resins, respectively. The determination of dye was performed at 483.0 nm using spectrophotometry. Validations of the methods were performed comparatively with determination of the sunset yellow content of some foodstuffs and pharmaceuticals.     

离子液体双水相萃取-HPLC测定饮料中的8种合成着色剂

试验旨在建立一种离子液体双水相萃取-高效液相色谱法检测饮料中8种合成着色剂(新红、靛蓝、胭脂红、日落黄、诱惑红、亮蓝、酸性红和赤藓红)的方法。考察了萃取剂的种类及体积、盐的种类及添加量、样品pH、萃取时间、离心时间对萃取效率的影响。在优化条件下,各物质在30~1200μg/L浓度范围内线性关系良好,相关系数均大于0.999,方法检出限为2.4~6.0μg/L。在加标量50,250和500μg/L水平下,样品加标平均回收率为86.5%~99.0%,相对标准偏差为0.3%~3.8%(n=6)。该法操作简单、迅速、环保且具有较高的萃取效率。     

双波长比值光谱法测定饮料中的色素

应用双波长比值光谱法测定了果味汽水、水果泡泡中胭脂红、日落黄、酒石黄的含量。依据该3 种色素的比值光谱特征,以日落黄为干扰组分,分别选择431、456nm 和509、525nm 为测定酒石黄和胭脂红的波长;以胭脂红为干扰组分时,选择514、535nm 为测定日落黄的波长。结果显示,酒石黄在0.1～60mg/L、胭脂红在0.2～80mg/L、日落黄在0.8～90mg/L 的质量浓度范围内线性关系良好,平均回收率分别是100.5%、101.1%和102.4%。本方法操作简便、易于推广,可应用于实际样品的检测。     

Quantitative determination of sunset yellow concentration in soft drinks via digital image processing

Image processing technique (IPT) can be used to evaluate the quality of food and drink products. Therefore, this study was focused on the relationship between colorimetric parameters of IPT and different concentrations of sunset yellow in Miranda soft drink. The amount of the sunset yellow color in Miranda soft drink were assessed using HPLC and a specific doses of 0, 25, 60, 90, 120 and 150 mg kg^?1 sunset yellow were maintained for this study. The image processing results showed that with increasing the concentration of sunset yellow, all colorimetric values were changed except for b* values. Regression analysis between colorimetric parameters and sunset yellow showed a significant multivariate linear relationship (P?<?0.05) with a high coefficient of determination (R² _adjusted?=?98.7). The results showed that the predictive equation could be used to estimate the concentration of sunset yellow color in Miranda soft drink. The result of the present study showed that digital image processing technique approach can be a successful tool for the prediction of sunset yellow concentration in drink products. Therefore, IPT could be a potential prediction tool for determining the quantity of synthetic colorant in the food and drink products.     

基于酸度控制的吸收光谱法测定饮料中共存的柠檬黄和日落黄

建立快速、准确测定饮料中共存着色剂柠檬黄与日落黄的吸收光谱检测方法。在一定酸度的Tris-HCl介质中，乙基紫与柠檬黄（pH 5.69）和日落黄（pH 8.68）反应生成离子缔合物，在波长506 nm处产生能定量分析共存色素中柠檬黄的特征吸收峰，在波长646 nm处产生能定量分析共存色素中日落黄的特征吸收峰，它们的表观摩尔吸光系数分别为1.37×105 L/（mol·cm）（柠檬黄体系）和7.68×104 L/（mol·cm）（日落黄体系）。柠檬黄在0.04～9.6 mg/L范围内与吸光度绝对值呈线性关系，检出限为0.024 mg/L，定量限为1.29 mg/kg；日落黄在0.04～6.3 mg/L范围内与吸光度呈线性关系，检出限为0.031 mg/L，定量限为1.68 mg/kg。该法用于实际样品分析，加标回收率为97.0%～104%（柠檬黄体系）和97.3%～103%（日落黄体系），相对标准偏差（n=5）为1.5%～2.6%（柠檬黄体系）和1.2%～2.6%（日落黄体系）。该法简便、快速，用于饮料中共存柠檬黄和日落黄的测定，结果满意。     

甲基绿吸收光谱法同时测定饮料中的酒石黄和日落黄

研究建立了一种简便、快速、能同时测定饮料中共存着色剂——酒石黄和日落黄的吸收光谱新方法。在pH 9.43 Tris-HCl溶液中,甲基绿与酒石黄和日落黄发生显色反应,生成离子缔合物,在400~750 nm范围内,酒石黄体系在574 nm波长处产生1个能进行定量分析的特征负吸收峰,共存色素日落黄不干扰测定,酒石黄的质量浓度在0.04~16.0 mg/L范围内与缔合物的吸光度绝对值(A)有很好的线性关系,表观摩尔吸光系数为4.90×10⁴ L/(mol·cm),检出限为0.033 mg/L,饮料的定量限为1.80 mg/kg;日落黄体系在488 nm波长处产生1个能用于定量分析的特征正吸收峰,共存色素酒石黄不干扰测定,日落黄的质量浓度在0.04~13.6 mg/L范围内与缔合物的吸光度有很好的线性关系,表观摩尔吸光系数为4.19×10⁴ L/(mol·cm),检出限为0.028 mg/L,饮料的定量限为1.51 mg/kg。该方法简便、快速,通过控制溶液酸度便可在不经分离的情况下同时测定同一饮料样品中共存色素——酒石黄和日落黄的含量。     

调味品中合成着色剂和糖精钠的测定

目的 建立了一种同时测定调味品中合成着色剂（诱惑红、胭脂红、日落黄）和糖精钠的高效液相色谱（HPLC）分析方法.方法 采用C18色谱柱,以甲醇和0.02 mol/L乙酸铵溶液为流动相,梯度洗脱,光电二极管阵列（PDA）检测器检测,采用外标法定量分析.结果 4种成分的线性范围为0.5～20.0 μg/mL （r＞0.999）,回收率为94.3％～101.6％,RSD为0.42％～2.44％（n=6）.结论 此法准确、灵敏,前处理简单,适用于调味品中诱惑红、胭脂红、日落黄和糖精钠的定性、定量分析.     

Automatic determination of nickel in foods by flame atomic absorption spectrometry

A new sensitive and low cost flow injection method that combines acid extraction, preconcentration and flame atomic absorption spectrometric determination of nickel in food samples at μg/g levels is described. The dynamic acid extraction step was carried out by using a continuous ultrasound-assisted extraction system. The acid extract was preconcentrated on-line on a minicolumn packed with a chelating resin (Serdolit Che, with iminodiacetic groups) and nickel was eluted with diluted hydrochloric acid, being continuously monitored by flame atomic absorption spectrometry. An experimental design (Plackett-Burman 2⁶ × 3/16) is used to optimise the methodology proposed. The method allowed a total sampling frequency of 13–28 samples per hour. Good precision of the whole procedure (1.9–3.6% expressed as relative standard deviation) and a detection limit of 0.12 μg/g, for 60 mg of sample were achieved. The method was successfully applied to the determination of trace amounts of nickel in food samples.     

Separation‐preconcentration of Cu,Cd, Pb and Ni in various water and food samples on Sepabeads SP‐207

This study presents a solid phase extraction (SPE) procedure for preconcentration and separation of Cu(II), Cd(II), Pb(II) and Ni(II), as their diethyldithiocarbamate chelates on Sepabeads SP‐207 resin using flame atomic absorption spectrometry. The parameters, including pH, sample volume, eluent type and volume etc., were optimised. The influences of the some alkali, alkali earth and transition metal ions on the involvement of copper(II), cadmium(II), lead(II) and nickel(II) were also examined. The preconcentration factor was calculated as 50. The limit of detections of the analyte ions (k = 3, N = 21) were 0.18 μg L^?1 (Cu), 0.17 μg L^?1 (Cd), 0.55 μg L^?1 (Pb) and 1.67 μg L^?1 (Ni). GBW 07605 Tea and NRCC‐DORM‐2 Dogfish Muscle certificated reference materials were used for confirm of method. The method was successfully performed for determination of Cu(II), Cd(II), Pb(II) and Ni(II) ions in water and food samples. The relative standard deviation was found to be lower than 7%.     

分散固相萃取-高效液相色谱法测定饮料和糖果中3种人工合成色素

以聚苯乙烯-聚4-乙烯基吡啶(PS@P4VP)复合微球为固相萃取材料,用于柠檬黄、赤藓红和日落黄3种人工合成色素的分析检测,探究了该微球的吸附性能与最佳固相萃取条件,建立了芬达(橙味)汽水和水果糖中3中色素的分散固相萃取-高效液相色谱(DSPE-HPLC)检测方法。结果表明,PS@P4VP对3种色素有较好的吸附性能,且可多次重复使用。柠檬黄和日落黄的最佳吸附pH为3.0,吸附平衡时间分别为20、90 min；赤藓红的最佳吸附pH为5.0,吸附平衡时间为60 min。PS@P4VP 对柠檬黄、赤藓红和日落黄的吸附过程均符合准二级动力学模型和Langmuir等温吸附模型,最大吸附容量分别为47.17、32.47、43.67 mg/g。结合实际样品分析结果表明,以PS@P4PV为固相萃取材料的高效液相色谱检测方法在芬达(橙味)汽水和水果糖中对3中色素有较好的分离检测效果,加标回收率为92.03~105.51%。     

Electrochemical sensor based on graphene and mesoporous TiO2 for the simultaneous determination of trace colourants in food

Currently, synthetic colourants draw much attention as food additives. This paper investigated the simultaneous electrocatalytic oxidation of sunset yellow and tartrazine, two yellow colourants commonly present in food together, with a novel voltammetric sensor based on graphene and mesoporous TiO₂ modified carbon paste electrode. Due to the high accumulation effect and great catalytic capability of graphene and mesoporous TiO₂, the developed sensor exhibited well-defined and separate square wave voltammetric peaks (i.e., 272 mV) for sunset yellow tartrazine. The peak currents of sunset yellow and tartrazine increased linearly with their concentration in the ranges of 0.02–2.05 μM and 0.02–1.18 μM, respectively. And the detection limit was 6.0 and 8.0 nM for sunset yellow and tartrazine, respectively. This new sensor was applied to determine sunset yellow and tartrazine in several food sample extracts. Results suggested that the proposed sensor was sensitive, rapid and reliable.     

饮料中日落黄盲样考核结果分析与评价

目的组织饮料中日落黄盲样考核活动,评价各食品实验室检测日落黄的能力与水平。方法设计2个浓度水平的日落黄盲样考核样品,并对样品进行均匀性与稳定性研究,获得各参加实验室检测结果,对结果进行稳健统计分析,通过Z比分数评价实验室的检测能力,并对结果进行分析。结果共有41家实验室参加了本次盲样考核,其中结果满意为33家,满意率为80.5%,结果可疑为3家,可疑率为7.3%,不满意结果为5家,不满意率为12.2%。结论参加本次盲样活动的实验室,多数实验室的检测能力评价为满意,表明各实验室具有饮料中日落黄的检测能力。但仍有部分实验室评价结果不满意,应分析原因并进一步提高实验室的检测能力水平。     

超高效液相色谱法同时测定包衣糖果中5种铝色淀

目的 建立包衣糖果中柠檬黄、日落黄、胭脂红、诱惑红和亮蓝5种铝色淀的超高效液相色谱测定方法.方法 用NaOH溶液浸泡提取包衣糖果中的色淀,以乙腈-乙酸铵(10 mmol/L)为流动相,梯度洗脱,多波长检测定量.结果 5种目标化合物在0.25～50 mg/L范围内呈良好的线性,相关系数R2 ＞0.999.该方法中5种目标化合物的定量限(LOQ)均为1.0 mg/kg.在1、5、25 mg/kg三个添加浓度水平下,5种目标化合物的加标回收率为79.5％ ～116.4％,RSD为0.92％ ～6.48％.结论 该方法简单、快速、准确,适于包衣糖果中5种铝色淀的同时检测.     

HPLC法检测蜜饯中20种合成着色剂含量

建立蜜饯中柠檬黄、新红、苋菜红、靛蓝、丽春红S、胭脂红、喹啉黄、日落黄、诱惑红、亮蓝、酸性红44、酸性红、食品红1、橙黄1、酸性红50、专利蓝V、赤藓红、酸性橙2、酸性橙8、亮蓝G共20种合成着色剂的高效液相色谱测定方法。试样用甲醇/氨水溶液提取,混合型弱阴离子反相固相萃取柱净化,甲醇/20 mmol/L乙酸铵为流动相梯度洗脱,二极管阵列检测器多波长检测,外标法定量。结果表明,该方法在0.1~20 μg/mL的线性范围内相关系数均大于0.999,加标回收率范围为84.0%~104.5%,相对标准偏差（RSD）为1.3%~5.3%。该方法操作便捷、稳定性好、回收率高,适用于蜜饯中20种合成着色剂的同时分析检测。该方法可以扩展应用于其他同结构性质的色素分析,对其他食品类别中色素的检测也具有参考意义。     

果汁饮料中合成色素检测方法的改进

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.     

高效液相色谱法测定饮料中12种水溶性合成着色剂

目的建立高效液相色谱法同时测定饮料中柠檬黄、喹啉黄、苋菜红、胭脂红、日落黄、诱惑红、酸性红、赤藓红、靛蓝、酸性绿S、亮蓝、专利蓝V 12种水溶性合成着色剂的方法。方法饮料样品经离心、过滤后直接进样,以甲醇-乙酸铵(0.02 mol/L)为流动相进行梯度洗脱,采用二极管阵列检测器多波长分析,外标法定量。结果 12种合成着色剂在0.5～100mg/L范围内线性关系良好,相关系数均大于0.999;检出限为0.05～0.3 mg/kg;平均回收率为91.0%～101.3%,相对标准偏差值为0.2%～2.3%。结论该方法简便、快速、准确,前处理简单,适合于基质成分较为简单的液体样品中多种着色剂的同时测定。     

Application of Dispersive Liquid–Liquid Micro-extraction Using Mean Centering of Ratio Spectra Method for Trace Determination of Mercury in Food and Environmental Samples

In the present study, dispersive liquid–liquid micro-extraction has been applied for trace extraction and determination of mercury (Hg) ions in environmental samples. The mean centering of ratio spectra method was used to optimize the experimental parameters affecting the extraction of Hg. The factors influencing the extraction procedure such as type and volume of extracting and disperser solvent, concentration of chelating reagent, pH, salt effect, and centrifuge time were investigated and optimized. Under the optimized conditions, the limit of detection of the method was 0.15 μg l^?1 and enrichment factor was 39. The calibration curve was linear in the range of 0.5–100 μg l^?1 with a correlation of determination (R ²) of 0.998. The relative standard deviation for determination of 40 μg l^?1 of Hg(II) was 2.6 % (n?=?5). The proposed method was applied for the determination of Hg in pine leaf, sea and river fish, sand, and water samples as indicators of environmental pollution and cigarette with satisfactory analytical results. In comparison with other methods, the proposed method is very simple, easy, rapid, and sensitive for determination of Hg at trace levels in complex matrices.     

Preconcentration of trace levels of cadmium (ІІ) ion using <Emphasis Type="Italic">Descurainia Sophia</Emphasis> seeds as a green adsorbent for solid phase extraction followed by its determination by flame atomic absorption spectrometry

For the first time, Descurainia Sophia (DS) seeds as an efficient and green adsorbent were used in solid phase extraction for preconcentration of trace levels of cadmium prior to its determination by flame atomic absorption spectrometry (FAAS). By using a batch method, Descurainia Sophia seeds were used as adsorbent to retain cadmium (??) ions in the sample solution. After eluting the adsorbent with 3 mol L^?1 HCl, the retained cadmium (??) was determined by flame atomic absorption spectrometry. Different parameters affecting the extraction efficiency such as pH, amounts of adsorbent, type and concentration of eluent solvent, extraction and desorption time were investigated and optimized. Under the optimum conditions, the calibration curve was linear in the range of 5–300 µg L^?1 cadmium (??) with a correlation coefficient of 0.998. The limit of detection (LOD) was 1.0 µg L^?1 and the relative standard deviation (RSD, %) based on seven replicate analysis of 25 µg L^?1 cadmium (??) was 3.2%. The accuracy of the proposed method was checked by the analysis of certified reference material (CRM) and spike methods. The results show a good agreement with certified values. The proposed method was successfully applied to determination of trace levels of cadmium in different water and rice flour samples.     

A Novel Electrochemical Sensor Based on Graphene Oxide Decorated with Silver Nanoparticles–Molecular Imprinted Polymers for Determination of Sunset Yellow in Soft Drinks

In this study, a new imprinted electrochemical sensor for selectively detecting sunset yellow was developed based on glassy carbon electrode (GCE) modified by graphene oxide decorated with silver nanoparticles–molecular imprinted polymers (GO/AgNPs–MIPs). GO/AgNPs were firstly synthesized using self-assembly technology, and GO/AgNPs–MIPs were synthesized through surface imprinted technology by using GO/AgNPs as the substrate and sunset yellow as the template, respectively. The sensor was prepared by a drop-casting method. The synthetic materials were characterized by transmission electron microscope (TEM), Fourier transmission infrared spectra (FT-IR), and X-ray diffraction (XRD). The sensor was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The usage amount of GO/AgNPs–MIPs suspensions, solution pH, and accumulation time made an important difference in the process of detecting sunset yellow. Under optimal conditions, the peak current is linear to concentration of sunset yellow in the ranges of 0.1–0.6 and 0.6–12 μM, and the limit of detection was estimated to be 0.02 μM (S/N = 3). Finally, the proposed sensor was applied to detect sunset yellow in soft drinks with acceptable recovery, which demonstrated that the sensor could be used as a reliable and simple method for practical detection of sunset yellow.