摘要
该研究建立高效液相色谱法快速测定荞麦制品中可可碱、咖啡因含量分析方法,采用甲醇∶水∶氨水(70∶3∶1,V/V/V)为提取液超声提取荞麦制品中的可可碱、咖啡因,在Shimpack VP–ODS色谱柱(250 mm×4.6 mm,5μm)上,以甲醇∶0.02 mol/L乙酸铵溶液为流动相进行梯度洗脱,紫外检测器275 nm波长检测。结果:采用外标法定量,该方法在0.25~50.0μg/mL浓度范围内有良好的线性关系,加标回收率均在97%以上,相对标准偏差不大于3.0%,可可碱最低检出限1.4 mg/kg;咖啡因最低检出限1.0 mg/kg,对荞麦制品中可可粉添加量的最低识别浓度为0.01%。结论:该方法具有快速、准确、灵敏度高,满足实验室日常鉴别荞麦制品中是否添加可可粉的工作需求。
a method was developed for the determination of theobromine and caffeine content of buckwheat products using high performance liquid chromatography. Method： the sample was ultrasonic extracted with methanol-water-ammonia water （ 70 ： 30 ： 1, V/V/V ）, and separated in Shimpack VP-ODS column （ 250 mm x 4.6 mm, 5 μm ） using methanol -0.02 mol/L ammonium acetate solution as mobile phase by gradient elution, and determined at 257nm by UV detector. Results： the calibration curve at the concentration range of 0.25~50.0 gg m1-1 was good linear. The recoveries of theobromine and caffeine in buckwheat products were above 97% and the relative standard deviation was not more than 3%. The lowest detection limit for theobromine was 1.4 mg/kg-~ and for caffeine 1.0 mg/kg. The lowest concentration of recognition for cocoa powder in buckwheat products was 0.0 1%. Conclusions： This method has the advantage of speedy, exactness and high sensitivity, which meets the demand of distin^uishin~ cocoa powder added or not in buckwheat products.
出处
《粮食与油脂》
北大核心
2013年第11期12-15,共4页
Cereals & Oils
基金
国家质检总局科技计划项目(2013QK203)
关键词
荞麦制品
液相色谱法
可可碱
咖啡因
buckwheat products
high performance liquid chromatography
theobromine
caffeine
作者简介
辛若竹（1969～），女，高级工程师，研究方向：食品营养与分析方面研究。
