The aim of this research was to evaluate the oxidative stabilities and qualities of different vegetable oils (almond, blend 1-8, camellia, corn, palm, peanut, rapeseed, sesame, soybean, sunflower, and zanthoxylum oil) based on peroxide value (PV), vitamin E content, free fatty acid, and fatty acid composition. The vegetable oils with different initial fatty acid compositions were studied under accelerated oxidation condition. It showed that PV and n-3 polyunsaturated fatty acid (PUFA) changed significantly during 21 d accelerated oxidation storage. Based on the changes of PV and fatty acid composition during the oxidation process, mathematical models were hypothesized and the models were simulated by Matlab to generate the proposed equations. These equations were established on the basis of the different PUFA contents as 10% to 28%, 28% to 46%, and 46% to 64%, respectively. The simulated models were proven to be validated and valuable for assessing the degree of oxidation and predicting the shelf life of vegetable oils.
The quality of edible oils is a very important aspect in marketing and human health. Variations of the natural lipid pattern of oil could affect its susceptibility and resistance to the oxidation process. In this study, a preliminary relationship based on fatty acid compositions and PV (a common and effective indicator used to measure lipid oxidation) was established under the oxidization conditions for the classification of vegetable oils. This method with proposed equations was proven to be a rapid way to evaluate and predict the degree of oxidation and shelf life of vegetable oils.