UTP University of Science and Technology, Faculty of Chemical Technology and Engineering, Seminaryjna 3, 85-326 Bydgoszcz, Poland.
UTP University of Science and Technology, Faculty of Chemical Technology and Engineering, Seminaryjna 3, 85-326 Bydgoszcz, Poland.
Carbohydr Polym. 2017 Jun 1;165:1-6. doi: 10.1016/j.carbpol.2017.02.029. Epub 2017 Feb 10.
A new approach to carrageenan quantitation was described. The method consists in titration of carrageenan solution by Methylene Blue dye or Toluidine Blue dye solution until a certain absorbance value. The optimal wavelengths are 660nm and 640nm when titrating with Methylene Blue dye and Toluidine Blue dye, respectively. Rectilinear calibration plots (R>0.996) provide carrageenan determination in the concentration range from 2 to 60mg/L with relative standard deviation from 1 to 5%. The proposed method is simple and feasible in use due to optical dip probe providing in situ absorbance measurements. The proposed way of end-point recognition as pre-set voltage is applicable with any automatic titrator. The method was tested on model jelly dessert sachet. No interference was registered from typical ingredients of jellies such as sucrose, citric acid, sodium citrate, malic acid, potassium sorbate as well as blue colorant. The neutral polysaccharides such as guar gum and locust bean gum have insignificant interference when their content is fivefold as compared to that of carrageenan.
一种新的卡拉胶定量方法被描述。该方法包括用亚甲蓝染料或甲苯胺蓝染料溶液滴定卡拉胶溶液，直到达到一定的吸光度值。用亚甲蓝染料和甲苯胺蓝染料滴定时，最佳波长分别为 660nm 和 640nm。线性校准曲线（R>0.996）提供了 2 至 60mg/L 浓度范围内的卡拉胶测定，相对标准偏差为 1 至 5%。由于光学探头提供原位吸光度测量，因此该方法简单可行。终点识别方法作为预设电压适用于任何自动滴定仪。该方法在模型果冻甜点小袋上进行了测试。从典型的果冻成分（如蔗糖、柠檬酸、柠檬酸钠、苹果酸、山梨酸钾以及蓝色着色剂）中未检测到干扰。当中性多糖，如瓜尔胶和刺槐豆胶的含量是卡拉胶的五倍时，它们的干扰可以忽略不计。
