Study of vegetable oils subjected to thermal stress

This study shows how canola, corn, olive, sunflower and soybean vegetable oils were studied, both in their natural state and under thermal stress. The application of hydrogen NMR proved to be essential in the quality control of vegetable oils, as it allowed the determination of the iodine index, the average molecular weight (MW) of triacylglycerol, the degree of unsaturation and the oxidation state of the oil in its natural state and under any heating time, which by traditional physical-chemical methods would be an arduous and imprecise task in many points of the quality analysis process. Similarly, C13 NMR proved to be very useful, as it showed significant variations in the C13 carbon profile of raw oils and under thermal stress. The results demonstrate that spectroscopic techniques are indispensable tools in the quality control of vegetable oils today.