直接光度法和酸度控制光度法相结合测定碳酸饮料中的共存色素  

Combination of direct photometry and acidity control photometry to determine coexisting pigments in carbonated drinks

作　　者：江虹[1] 庞向东[1] JIANG Hong;PANG Xiangdong(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》2021年第19期271-276,共6页Food and Fermentation Industries

基　　金：重庆市教委科技基金资助项目(S201910647003);长江师范学院科技基金资助项目(2018CXX111)。

摘　　要：结合定性和定量的方法,建立测定几种碳酸饮料中共存色素——亮蓝、柠檬黄和日落黄的简便吸收光谱法。直接法测定亮蓝,其最大吸收波长为628 nm,表观摩尔吸光系数(κ)为1.20×105 L/(mol·cm),检出限为0.018 mg/L,线性范围为0.02~15.4 mg/L,饮料的定量限为0.31 mg/kg。酸度控制法测定柠檬黄和日落黄(亮蓝不干扰),在pH 3.50 Tris-HCl条件下,灿烂绿与柠檬黄和日落黄反应,生成离子缔合物,柠檬黄体系的最大吸收波长为426 nm,κ为2.59×10^(4) L/(mol·cm),检出限为0.028 mg/L,线性范围为0.03~13.4 mg/L,饮料的定量限为0.47 mg/kg;日落黄体系的最大吸收波长为500 nm,κ为1.46×10^(4) L/(mol·cm),检出限为0.030 mg/L,线性范围为0.03~8.14 mg/L,饮料的定量限为0.51 mg/kg。该法测定饮料中共存色素——亮蓝、柠檬黄和日落黄,简便、快速,结果满意。Combining qualitative and quantitative methods,a simple absorption spectrometric method for the determination of coexisting pigments in several carbonated beverages—brilliant blue,tartrazine and sunset yellow was established.The direct method was to measure bright blue under the following conditions:maximum absorption wavelength was 628 nm and the apparent molar absorption coefficient(κ)was 1.20×105 L/(mol·cm).The detection limit reached 0.018 mg/L,the linear range was 0.02-15.4 mg/L and the quantitative limit of beverages was 0.31 mg/kg.Moreover,the acidity control method was used to determine tartrazine and sunset yellow(bright blue didn't interfere).Under the condition of pH 3.50 Tris-HCl,brilliant green reacted with tartrazine and sunset yellow to form an ionic association complex.The maximum absorption wavelength of the tartrazine system was 426 nm,theκwas 2.59×10^(4) L/(mol·cm),the detection limit was 0.028 mg/L,the linear range was 0.03-13.4 mg/L,and the quantitative limit of beverage was 0.47 mg/kg.In addition,the maximum absorption wavelength of the sunset yellow system was 500 nm,theκwas 1.46×10^(4) L/(mol·cm),the detection limit was 0.030 mg/L,the linear range was 0.03-8.14 mg/L,and the quantitative limit of beverage was 0.51 mg/kg.This method developed here was simple and rapid for the determination of coexisting pigments in beverages—brilliant blue,tartrazine and sunset yellow,with satisfactory results.

关 键 词：碳酸饮料 亮蓝 柠檬黄 日落黄 灿烂绿 吸收光谱法 

分 类 号：TS27[轻工技术与工程—农产品加工及贮藏工程] O657.3[轻工技术与工程—食品科学与工程]