This difference between the values of acidity is indicative of polyphenols ability to retard oils oxidation causing the fatty acids releasing. reported the effectiveness of reaction add to palm oil and use to fry potatoes for about 32 h where the acidity for this oil and the control is about 0.42% and 0.59% respectively.
The oil hydrolysis caused by the water effect introduced by the fried food is a phenomenon that does not occur during our study because the heating was conducted in the absence of food. The increase in free fatty acids value is attributed in this study mainly to the degradation of secondary oxidation products formed during heating and the presence of oxygen. The moisture that may be provided by air could have an influence on increasing acidity.