甲基绿双波长吸收光谱法测定面制食品中甜蜜素  

Determination of cyclamate in flour foods by dual-wavelength absorption spectroscopy with methyl green

作　　者：刘艳[1] 庞向东[1] 陈明朗 江虹[1] LIU Yan;PANG Xiangdong;CHEN Minglang;JIANG Hong(College of Chemistry and Chemical Engineering,Yangtze Normal University,Chongqing 408100,China)

机构地区：[1]长江师范学院化学化工学院,重庆408100

出　　处：《食品与发酵工业》2020年第7期244-249,共6页Food and Fermentation Industries

基　　金：重庆市教委科技基金资助项目(KJ1401226);长江师范学院科技基金资助项目(2018CXX117)。

摘　　要：建立一种快速、准确测定面制食品中的食品添加剂--甜蜜素的双波长可见吸收光谱法。在弱碱性Tris-HCl介质中,甲基绿与甜蜜素以静电相吸作用在可见光区生成具有2个特征正吸收峰的离子缔合物,分别位于616 nm和652 nm,其表观摩尔吸光系数(κ)分别为2.66×10^4L/(mol·cm)(616 nm)和2.14×10^4L/(mol·cm)(652 nm),线性范围均为0.05~2.8 mg/L,检出限分别为0.042 mg/L(616 nm)和0.046 mg/L(652nm),饼干的定量限分别为3.47 mg/100 g(616 nm)和3.80 mg/100 g(652 nm),面包的定量限分别为3.45mg/100 g(616 nm)和3.78 mg/100 g(652 nm)。当以双波长616 nm+652 nm可见吸收光谱(dual-wavelength visible absorption spectroscopy,DWO-VIS)法测定时,表观摩尔吸光系数(κ)和检出限分别为4.80×10^4L/(mol·cm)和0.022 mg/L,饼干和面包的定量限分别为1.82 mg/100 g和1.81 mg/100 g,样品的加标回收率为97.5%~103%,相对标准偏差(n=5)为1.4%~2.3%。该方法简便、快速,有较高的准确度、精密度和灵敏度,适于饼干和面包中甜蜜素的检测。A rapid and accurate dual-wavelength visible absorption spectroscopy for the determination of food additive-cyclamate in flour foods was established.In the weakly alkaline Tris-hydrochloric acid medium,methyl green reacted with cyclamate by electrostatic attraction to form an ion association complexes with two characteristic positive absorption peaks in the visible region.These two characteristic peaks were located at 616 nm and 652 nm,respectively.Their apparent molar absorptivity(κ)were 2.66×10^4 L/(mol·cm)(616 nm)and 2.14×10^4 L/(mol·cm)(652 nm),respectively.Their linear range were 0.05 to 2.8 mg/L,the limits of detection were 0.042 mg/L(616 nm)and0.046 mg/L(652 nm),respectively.The limits of quantitation of biscuits were 3.47 mg/100 g(616 nm)and 3.80 mg/100 g(652 nm),respectively.The limits of quantitation of bread were 3.45 mg/100 g(616 nm)and 3.78 mg/100 g(652 nm),respectively.When measured by dual-wavelength(616 nm+652 nm)visible absorption spectroscopy,its apparent molar absorptivity(κ)and detection limits were 4.80×10^4 L/(mol·cm)and 0.022 mg/L,respectively.The quantitative limit of biscuits and bread were 1.82 mg/100 g and 1.81 mg/100 g,respectively.The spiked recovery of the sample was 97.5%-103%,and the relative standard deviation(RSD)(n=5)was 1.4%-2.3%.This method(DWO-VIS)was simple,rapid,and higher accuracy,precision and sensitivity.It was suitable for the detection of cyclamate in biscuits and bread.

关 键 词：甜蜜素 甲基绿 饼干 面包 双波长 吸收光谱法 

分 类 号：O657.3[理学—分析化学] TS213.2[理学—化学]