色素類の赤外部吸収スペクトルによる分析的研究 (第3報)

赤色食用色素およびRhodamine Bについて

抄録

The method of quantitative and qualitative analyses by the use of infrared absorption spectra was examined for dyes used for foodstuff (Ponceau 3R, Amaranth, Erythrosine, Ponceau SX, Oil Red XO, Ponceau R, New Coccine, Eosine, Phloxine, Rose Bengal, and Acid Red) and one not used for foodstuff (Rhodamine B). Each of these dyes was able to be identified in a limit of 40-300γ by the characteristic bands (Table I). Attempted quantitative determination of Rose Bengal (I) and Rhodamine B (II) showed that they can be determined by the use of a characteristic band at 961cm^-1 for (I) with standard deviation of 0.519 and at 1078cm^-1 for (II) with standard deviation of 0.633. Separately determination of a mixture was tested with a mixture of (I) and (II). The key bands used were that at 961cm^-1 for (I) and at 1078cm^-1 for (II), and standard deviation of analytical result of each component in the mixture was presumed from Youden's method, by which quantitative determination was found possible with standard deviation of 0.624 for (I) and 0.659 for (II).