A comparative study on the physio-chemical properties of vegetable oils

Project Abstract

This research project aimed to conduct a comparative study on the physio-chemical properties of vegetable oils commonly used in cooking and food preparation. The vegetable oils analyzed in this study included olive oil, coconut oil, sunflower oil, and canola oil. The physio-chemical properties that were investigated included the fatty acid composition, iodine value, saponification value, acid value, and peroxide value. The results of the study revealed varying fatty acid compositions among the different vegetable oils. Olive oil was found to be rich in monounsaturated fatty acids, particularly oleic acid, while coconut oil was predominantly composed of saturated fatty acids. Sunflower oil and canola oil contained higher levels of polyunsaturated fatty acids, with sunflower oil being rich in linoleic acid and canola oil containing significant amounts of oleic and linoleic acids. In terms of iodine value, sunflower oil had the highest value, indicating a higher degree of unsaturation compared to the other oils tested. Canola oil also showed a relatively high iodine value, while olive oil and coconut oil had lower values, consistent with their fatty acid compositions. The saponification values obtained in this study reflected the average molecular weight of the fatty acids present in the oils. Canola oil exhibited the highest saponification value, followed by sunflower oil, olive oil, and coconut oil, in decreasing order. These findings aligned with the fatty acid profiles of the oils, as oils with higher molecular weights of fatty acids tend to have higher saponification values. Furthermore, the acid values determined in the study indicated the amount of free fatty acids present in the oils. Coconut oil displayed the lowest acid value, suggesting a lower degree of hydrolysis and rancidity compared to the other oils. Sunflower oil had the highest acid value, indicating a higher level of free fatty acids, while canola oil and olive oil fell in between, showing moderate acid values. Lastly, the peroxide values measured in this study served as an indicator of primary oxidation in the oils. Coconut oil exhibited the lowest peroxide value, indicating better resistance to oxidation, while sunflower oil had the highest peroxide value, suggesting a higher susceptibility to oxidation. Canola oil and olive oil showed intermediate peroxide values, reflecting their oxidation stability. Overall, this comparative study provided valuable insights into the physio-chemical properties of different vegetable oils, highlighting their unique compositions and characteristics that influence their quality and suitability for various culinary applications.

Project Overview