Abstract
Various determination methods for alginic acid have been developed for specific samples. As we were unable to directly compare the results of these methods, we developed a novel determination method. The procedure is as follows : ① extraction of dietary fiber fraction from samples ; ② selective extraction of alginic acid from the dietary fiber fraction ; and ③ colorimetric determination of alginic acid by carbazol-sulfuric acid reaction. When kelp (alginic acid content : 26.6g/100g) assessment was repeated 7 times, the intermediate precision (relative standard deviation) was 2.1%. The lower limit of determination was 0.1g/100g when using dextrin as a blank sample. Based on the present results, the trueness (mean recovery) ranged from 67.3% to 99.2% for 7 types of food.
