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In India, people have become thoughtful about the safety and nutritional value of the food they are eating, thanks to the various food safety controversies going on!
While carefully choosing a good cooking oil, the rancidity of the oil is also of prime importance as, when the oil is heated at high temperatures, it breaks-down and becomes rancid and toxic for health.
What about Refined Oils and Rancidity?
Refined cooking oils are processed by highly intensive mechanical and chemical ways to remove the oil from the seeds. These processes often involve heating and resultant oxidation. The oxidation makes these oils more likely to create cancer causing free radicals within the body.
Are Hydrogenated Oils rancid ?
During hydrogenation, oils are converted to solid form for ease of use. Extracted oils are mixed with metal particles and treated with high-heat and pressure along with hydrogen gas. Emulsifiers are added to the mixture which is then steam-cleaned to remove rancid odors. It is then bleached and artificial dyes and flavorings are added.
Better oils to consume
An example of a better cooking oil is unrefined coconut oil, which is less processed and also has a higher heat threshold.
People like to cook with olive oil, but it is not the best option due to the lower heat threshold it has. Olive oil can be used in salad dressings or other dishes that aren’t exposed to high levels of heat.
Butter is full of fat-soluble vitamins and minerals which are difficult to obtain from other sources. Butter can be used where high heat is not required. Margarine or other artificial fats should never be used as margarine contains toxic trans-fats.
Sources:
http://www.livestrong.com/article/459786-can-you-get-sick-from-eating-rancid-oil/