Edible oils are the most concentrated source of metabolic energy among carbohydrates, proteins and lipids which are available through food to humans. Oils and fats contain more than twice the caloric value of equivalent carbohydrates or proteins. Their functional and textural characteristics contribute to the flavor and palatability of natural and prepared foods. They contain certain fatty acids which play an important role in nutrition and are also carriers of fat-soluble vitamins. The beneficial applications of essential fatty acids like unsaturated fatty acids on human health have increased the market and market value for the edible oils (FAO, 2011).

Reusing edible oil for preparing food, particularly in deep-frying, is a common practice of food venders to enhance the profit. The oxidative degradation of oil lipid accelerates during repeated heating and forms hazardous reactive oxygen species and also diminishing the natural antioxidant contents of the edible oil. During the deep frying of food, cooking oil is exposed to a very high temperature, a series of complex chemical reactions take place, following in loss of both quality and nutritional values of the cooking oil eventually producing free radicals. (Gogus & Smith, 2010).

Recently, food vendors and restaurant owners in Bangladesh have queries about the repeated use of edible oils as they are being punished due to using the same oil for several times. But due to the lack of researches and data, the Government is facing problems in providing them with authentic answers. This study aims to find out the degree of repeated use of the edible oils (soybean oil, palm oil and rice bran oil) that will leave no health risks during cooking. Again, repeated heating brings several changes in the fatty acid profile of the oils. As a result, some valuable fatty acid may not be found after cooking. This study targets to find out the changes in fatty acid profile of the locally consumed edible oils to show whether there is any significant changes occur in the nutritional values of the oils.