利用光学旋转和折射率检测对茶叶中的糖进行分析

感光旋转探测器可用于光学活性材料的选择性检测。采用感光旋转检测器（OR）和折射率检测器（RI）的组合方法对红茶和柠檬茶中的糖进行了分析。Application Note 2/3Application NoteSugar Analysis in Tea using Optical Rotation and Refractive Index Detection Sugar Analysis in Tea using Optical Rotation and Refractive Index detection Intr o d u cti o n An optical rotation detector can be used for selective d e tection of optically active materials. T h e sugar i n black and lemon teas were analyzed using a combination of optical rotation detector (OR) and re f ractive index detector (RI ). Figure 1 Chromatogram of a standard sample .Meso -erythritol is optically inac t iveand can only be detected by refractive in d ex. Jasco OR 2090 Figure 2 chromatograms of sugar -f ree black tea and lemon tea. Keyword： 1. Tea， 2. Sugar， 3. Optical Rotation， 4. Refractive I n dex 5. HPLC 6. Finepak amino column 7. Meso-Erythritol， 8. D-Xylose， 9. D-Fructose， 10. D-Glucose， 11. D-Sorbitol， 12. D-Sucrose. Condi t ions Column Temp： Injection Volume： Figure 1. Chrom a t o gram o f a st a ndard sa m pl e . 1. mes o -Er y t hr itol， 2. D-Xy l os e ， 3. D-Fructos e ， 4. D-G lu co se ， 5. D-S o r bi t o l， 6. D-S u crose Figure 2， Limonene and Carvone have very similar UV spectra， but show differences in the IR. Co -elution in the chromatogram detected using UV as shown i n figure 3 and 4 illustrates the i nability of using UV to trigger fraction col l ection. Figure 5 shows IR chromatograms at t wo different wave number ranges and the fractions collected using those chromatograms. A Carvone sta n d a rd and Spearmint oil were separated using HPLC and fraction s 1an d 2 were compared to confirm the separation and purity as seen in Figure 6. Figure 2. Chromatog r a m o f tea samples. 1. m eso-Erythri to l， 3. D-Fruc to se， 4. D-Gl u cose， 6. D -Sucrose