- 一般社団法人 日本調理科学会
- 調理科学 (ISSN:09105360)
- vol.26, no.1, pp.12-26, 1993-02-20 (Released:2013-04-26)
The conditions of quantitative analysis of vitamin C in foods by Fujita's method of thin layer chromatography were investigated and the following improvements were made.1) The drying step of ethylacetate dissolving osazon can be omitted.2) The thin layer after development is able to be left alone for 2 days before starting the next step.3) The fraction of vitamin C can be dissolved with 50% sulfuric acid without any trouble.4) Silica gel should be removed by the use of a glass filter.The amount of vitamin C in foods was determined by subtracting the amount of diketoglonic acid which was estimated from the remaining amount following reduction of an aliquot portion of the test sample according to Tamura's method from the amount of vitamin C determined by this modified method.The remaining amounts of vitamin C in some fruits and vegetables such as broccoli, were determined under various cooking conditions; without heating, heating at 100°C pH-changing etc. From the present results, it was demonstrated that the amount of vitamin C in foods including ascorbinase varies considerably and vitamin C tends to be short of stability at cooking.