Abstract
In 1960,F.J. Mulder of Philips-Duphar visited Japan, and introduced the vitamin A determination using saponification, benzene extraction, and determination of the extinction at 310,325,and 334 mμ on the isopropyl alcohol solution of unsaponifiable matter. We have tried out the whole oil method, USP method, and Mulder's method on USP vitamin A reference standard solution. When setting the results of the whole oil method as 100,USP method gave 99.2 and Mulder's method as 102.9. Similar results were obtained when various vitamin A preparations were tested. The reason of high value by Mulder's method is due to concentration of benzene solution during the determination. This high value (2〜3%) may be neglected in view of the permissible deviation in vitamin A determination, but Mulder's method gives more accurate value when multiplied factor 0.98.
