Cold pressed oil: Why you should switch from refined oil to this much healthier alternative
Do you remember your grandparents/parents telling you about how they used to go to the store with an empty can to purchase chekku ennai for Rs. 5/- a pail? In South India, chekku ennai was a way of life until 50 years ago when industrially processed, refined oils took over the market.
Chekku ennai is the local name for cold pressed sesame oil. But what’s so special about cold pressed oils?
Conventional oil extraction
The modern method of oil extraction involves supplying a lot of heat. The oilseed is first crushed, and the pulp is heated under pressure. As a result, almost all the oil is extracted.
The downside is that the oil is heated up to temperatures of 230 degree centigrade. Heating it to such high temperatures alters the properties of the oil molecules in unfavourable ways (Polycyclic Aromatic Hydrocarbons are formed at high temperatures which are carcinogenic) – and strips it off of its nutritional value.
For optimum extraction of oil, a solvent is added, in this case, hexane. The hazards of exposure to hexane are many – including dermatitis and CNS depression – depending upon the quantity of hexane inhaled or ingested.
The other option of extraction is using a method called “Expeller pressing“, which is a mechanical process of extraction using a machine called an expeller. No heat is added to the process, but heat can be produced as a result of the mechanical action on the nut – which could very well result in high temperatures that alter the chemical composition of the oil.
After subjecting the oil to such high temperatures, manufacturers tend to use preservatives to prevent the oil from becoming unstable. There is inconclusive evidence about whether these preservatives are harmful, but toxicology studies advise that it’s better to stay away from them.
Oils that have been refined through this process stay longer on the shelves and are more stable. This, however, is at the cost of its nutritional value.
The case for cold pressed oils
In olden times, a long cylindrical contraption called a “ghani” was used. The oilseeds were placed inside and ground with a pestle until the oil came out. This is the simplest method for “cold-pressing” the oil out of a seed because it doesn’t involve the generation or addition of heat. The residue or the oil cake was used as fodder for cattle.
Today cold-pressed methods of extraction are the same as the expeller-pressed method, albeit in a temperature-controlled setting. According to the European Union regulations, the temperatures for cold-pressing must not exceed 27 degrees centigrade, though such criteria in India have not been established.
So why must we include organic cold pressed oils in our cooking?
1) They retain healthy anti-oxidants that are otherwise destroyed by heat. These anti-oxidants fight harmful free radicals and prevent the growth of tumors.
2) Cold pressed olive oil is rich in Vitamin E, which has anti-inflammatory, healing properties. It is a good source of oleic acid which strengthens the immune system.
3) Cold pressed coconut oil, despite its bad reputation, contains lauric acid, which fights against harmful pathogens. This compound is also found in human breast milk. According to this article, “Coconut oil contains a lot of medium chain triglycerides, which are metabolized differently and can have therapeutic effects on several brain disorders.”
4) Rujuta Diwekar, in her article for Outlook recommends cold-pressed filtered groundnut oil. “At low temperatures, the fatty acid bonds in the groundnut don’t get destroyed, keeping its heart-protecting abilities intact, along with vitamins and minerals. Groundnuts, with their high Niacin (of the Vitamin B family) content, help stabilise blood sugars”, she writes.
Cold-pressing eliminates all the harmful effects that arise from the conventional methods of oil extraction. The only problem with cold pressed oils is their short shelf-life.
However, an organic producer of cold pressed oils said that if stored in clay utensils, chekku oil lasts for almost a year. Chekku oil is traditionally supplemented with palm sugar or jaggery, which heightens its flavor and also its nutritional value.
To be cautious, always buy cold pressed oil in small quantities, store it away from light, in air-tight containers, and consume it within three months of purchase.
And remember to buy organically sourced cold pressed oils that are free of pesticides to reap the full benefits of cold pressing (look for one of the “India Organic” certifications on the label to confirm that it’s organic). These are good for your heart, your overall well-being, and your grandparents will be proud!