PhD Oral Defense: Deep-fat frying characteristics of blends of palm and canola oils
PhD Oral Defense of Ogan Iheanacho Mba, Department of Bioresource Engineering
Selecting an appropriate oil for commercial deep-fat frying can be challenging. Commercial frying began with animal fats. Next, partially hydrogenated vegetable oils were commonly used. Due to the high temperature, the presence of oxygen, water, and other compounds from the food being fried, the frying oil undergoes thermo-oxidation induced irreversible degradation reactions. The highly-saturated animal fats and trans-fatty acids that come with hydrogenation procedures have adverse public health consequences. Oils with higher unsaturation are more susceptible to thermo-oxidation reactions. On the other hand, omega-3 and omega-6 monounsaturated fatty acids have proven health benefits, demand for natural products has been rising, and emphasis on nutritional enrichment has been increasing. The food industry has been exploring alternatives that address both public health concerns and improves frying process and products. The use of minimally processed stable oils, blending different oils in a frying medium, and breeding oil seeds with altered fatty acid composition appear to be the most viable cost effective alternatives to animal fats and hydrogenated vegetable oils. Virgin palm oil (VPO) has a balanced composition of saturated and monounsaturated fatty acids. It is very rich in endogenous phytonutrients (such as carotenoids, tocopherols and tocotrienols) with biological activity and health-promoting functions. This study investigated the stability of these phytonutrients and the extent of the phytonutrients’ migration into fried products when VPO is used either alone or as the major component in blends of oils in deep-fat frying operations. Refined canola oil (RCO) was used as the second oil sample in the binary blends.