摘要
基于过氧化钙(Ca O2)在酸性介质中可生成过氧化氢,过氧化氢在辣根过氧化物酶(HPR)的催化作用下,以KI为增敏剂,可快速氧化季胺[4,4’-(二甲氨基)-二苯基甲烷]显色的原理,建立了小麦粉中Ca O2定性测定的目视比色法和定量测定的分光光度法。研究了HPR用量、KI用量、季胺用量、p H值、反应温度和反应时间对显色的影响,并对测定条件进行了优化。结果表明:在最优化实验条件下,显色体系的颜色随Ca O2标准使用液浓度的升高而加深,根据颜色的渐变与Ca O2浓度的关系制作了目视比色测定的标准比色带;且显色体系吸光度在Ca O2浓度0 mg/L^9 mg/L范围内符合比尔定律,线性回归方程为+=Δ0052.0C107.0A,R2=0.9994。该法用于实际样品的分析,目视比色法可快速确定Ca O2的含量范围,分光光度法检出限为1.64×10-2 mg/L,加标回收率为96.3%~101.7%,RSD为1.74%~3.15%。
As calcium peroxide can generate hydrogen peroxide in an acidic medium, visual colorimetry for rapid qualitative analysis and spectrophotometry for quantitative analysis of calcium peroxide in wheat flour were established based on the principle that hydrogen peroxide can cause rapid oxidation and chromogenesis in quaternary amine [4,4′-(dimethyl amine)diphenyl methane] by using horseradish peroxidase(HPR) as the catalyst with KI as the sensitization agent. In this study, the experimental conditions for detecting calcium peroxide were optimized, and the experimental factors influencing chromogenesis, including the HPR content, KI content, quaternary amine content, p H, reaction temperature, and reaction time, were investigated. The results showed that under the optimum conditions, the color of the complex gradually deepened with increasing calcium peroxide content. Based on the relationship between the color gradients and concentration of calcium peroxide, a standard color card was created for visual colorimetric determination. Beer's law was obeyed when the concentration range of calcium peroxide was within 0~9 mg/L. The linear regression equation was as follows: ΔA = 0.0052 + 0.107 C, with a correlation coefficient of 0.9994. The recovery rate for spiked standards was within 96.3%–101.7%, and the relative standard deviation was 1.74%~3.15%. The range of calcium peroxide content was rapidly determined by visual colorimetry and its detection limit was 1.64 × 10-2 mg/L.
出处
《现代食品科技》
EI
CAS
北大核心
2015年第5期262-266,共5页
Modern Food Science and Technology
关键词
小麦粉
过氧化钙
测定
目视比色法
分光光度法
wheat flour
calcium peroxide
determination
visual colorimetry
spectrophotometry
