Chemical refining of sunflower oil: effect on oil stability, total tocopherol, free fatty acids and colour

The effect of chemical refining on oil stability index of sunflower oil and other quality attributes free fatty acids, total tocopherols, colour and was investigated. The results revealed that all these quality attributes are decreased during the chemical refining process, except oil stability which was decreased during neutralizing, bleaching and winterizing step, however it was increased in deodorizing step. Deodorization step has a significant effect on all of these quality attributes. Results of this study indicated that, most part of the tocopherols are wasted during deodorizing step. Therefore, oil stability not always in depends on the content of tocopherol, however the proper concentration of nutritionists, industrialists, and manufacturers are also needed for the necessary improvements in processing technology to avoid the major loss of tocopherols and to increase the shelf life, as well as the, nutritive value of processed oil.