Tocopherols and tocotrienols are important minor compounds in vegetable oils with a concentration of 200-1500 ppm . They show a high anti-oxidant and vit. E acitivity. Therefore they are used as nutraceutcals in human nutrition and health. However refining of crude oils has a high influence on the content of the tocopherols in refined oils. Especially during the deodorization (process condtions : ( 220-250°C, 1 mbar, 1 % steam, 40-60 minutes) tocopherols are partioned in the refined oils and in the deodorizer distillate (DOD). A significant loss in the tocopherol mass balance in the range of 25-35 % is observed due to the chemical instability of the tocopherols and the process conditions. At high temperatures and in the presence of traces of oxygen tocopherols are oxidized in a series of compounds such as dimers, tocopherol quinones and epoxytocopherol quinones. Experiments using a variety of process conditions show that high temperatures, the presence of anti-oxidants and the absence of oxygen has very little influence on the stability. In addition the stability of tocopherols seems to be dependent upon the unsaturation level of the oil. Tocopherols and tocotrienols can be isolated from the DOD. An alternative two step deodorization technique will be presented allowing a high retention in the refined oil but also a high concentration of the tocopherols in one of the two fractions of DOD. This new process is using a short time- high temperature and and a long time - low temperature profile. Also pressing or solvent extraction of the seeds gives a slightly higher concentration of tocopherols in solvent extracted oils. Also it has been observed that the presence of oxygen in bottled oils has a dramatic effect on the concentration of the tocpherols and tocotrienols. Using optimal refining conditions and isolation techniques an excellent retenion of tocopherols in the refined oil and an efficient resources for tocopherols and tocotrienols are observed

Influence of refining of vegetable oils on the stability, isolation and nutritional quality of tocopherols and tocotrienols

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.