The market for oils for cooking, is becoming very confusing. Whilst many are aware that some good oils are important for normal body functions, what constitutes good is debatable, as manufacturers justify why consumers should be using their oil.
Recently, there has been a lot of debate as to the claim made by coconut oil to be a healthy oil. The rationale for the doubt creation is that there is not enough research to prove it. How much research is adequate is dependent on who’s looking at it and what you are looking for. In our quest to combat heart disease and move away from saturated fats (butter and lard) to polyunsaturated fats in the last 30 or so years, the incidence of heart disease has not decreased, if at all it has increased!
I invite you to look at the biochemistry of oil, of saturated fats and unsaturated fats. What differentiates them is the number of double bonds in the chain. The main fat in coconut oil is lauric acid. Coconut oil is a medium chain triglyceride, is easy to process and goes straight to your liver to produce energy, rather than stored. It is easy to digest and supports thyroid function. Coconut oil can withstand heating.
Olive oil is a monounsaturated fat, which means it contains a double bond, if you break it, you degrade the quality of the oil. This is a good fat when used in low temperature cooking or in salads, not in high heat.
Rice bran oil has been a favourite, marketed for it high heat properties. I have been asked often if rice bran oil is a good oil for cooking. Information I have been able to access states that approximately half the oil is polyunsaturated and the half monounsaturated, so using biochemistry, is not an ideal oil for heating, because of the many double bonds that the polyunsaturated part of the oil contains. However, rice bran oil claims a high smoking point. Smoking point is increased in refined oils, i.e. the process of bleaching and filtering the oil from the naturally occurring ingredients like proteins, enzymes and minerals in the oil increases the smoking point. The process of bleaching and filtering will result in an oil that is more neutral in taste, has a higher smoking point and longer shelf life. So the higher smoking point in rice bran oil will be from the refining process to allow for that to happen.
Soy, canola and corn oils are polyunsaturated fats. They are heavily traded commodities, which makes genetic modification appealing for commercial purposes. I do not favour these oils for cooking. Some other fats I advise staying away from are margarines. These products often have a Heart Foundation Tick, with very little saturated fats, but are highly processed. How do you convert a liquid oil at room temperature into a solid form? Solidification or hardening. I’m not sure that the hardening of the liquid oil is not hardening our arteries as well!
In short, I would recommend using coconut oil for high heat cooking and olive oil for salads and stir frying or steam frying.