Purification of tocochromanols from edible oil

Enriching Vitamin E from its natural sources, i.e., edible oils, and in its original, natural homologous matrix is becoming increasingly desirable. Supercritical fluid extraction (SFE) offers several advantages over conventional techniques such as vacuum distillation. In this paper, results are presented that were obtained in the course of investigating two different feed materials, namely crude palm oil (CPO) and a soy oil deodorizer distillate (SODD). CPO contains several tocochromanols at a concentration of approximately 500 ppm. The investigated SODD contains approximately 50 wt.% tocochromanols. Thus, this work allows conclusions about the Vitamin E extraction over the entire concentration range. Phase equilibrium measurements were conducted in order to obtain basic data in respect to gas load and distribution coefficient. This data allowed the theoretical description of the separation process within the scope of a separation analysis, eventually yielding in optimum extraction conditions and column design parameters. The results were subsequently verified experimentally by employing a 6 m SFE column in pilot scale. The results show that the Vitamin E enrichment is well within the ability of SFE techniques.