Vegetable oils are an essential source of energy for the human body. Therefore, it is considered one of the essential components of food. The process of frying is one of the most food operations in Iraqi kitchens. The repeated heating of edible oils causes a change in the physical properties of these oils. This study attempts to pay attention to these changes in physical properties, such as color, concentration, and smile. Adopted the spectroscopic method to study the changes resulting from the heating of edible oils and adopted olive oil because it has the specifications of the important between edible oils used in frying. It was found that heating these oils to a temperature higher than 100 degrees Celsius cause significant changes in the spectral structures which are the reflection of the chemical composition, i.e. the heating may be changed the structures of oils and perhaps toxic.

Olive Oil, Photophysical Properties, Temperature Effect.