It is better to spend on oil traders than to a doctor is a proverb. It implies that buying low quality products and thereby inviting health complications, eventually spending on doctors is imprudent. Having said that it is very much appropriate when it comes to choosing specific type of oil in our day to day life. Preparation of most of the food products and dishes in India use oils to a considerable extent, particularly the fries and snacks where we expect more crispiness that is imparted due to use of oil. Further, it is commonly believed that more oil will lead to better taste. But the type of oils and their quality, most importantly their processing methods matter a lot while choosing a particular kind of oil from the market to our kitchen, as they have their direct influence on one’s health.
Common notion is that the refined oils that look visually pure, crystal clear, assuring stability with long shelf life, often double refined, are good, especially conducive to our cardio vascular systems. One needs to consider many confounding factors, for and against, whether to use refined or traditionally pressed oil types. Popularity of refined oils is just a few decades old while the traditionally pressed oil is many centuries old. In general, refined oil is chemically processed, often by using solvent to extract oil from the oil seeds, using hi-tech machineries. The traditional oil pressing involve low end machineries that use force and pressure to extract out oil. In both the processes considerable heat is generated that could affect the beneficial composition of the extracted oil; heat used in refined oil processing is higher than the traditional oil pressing.
Comparatively, the process of traditional pressing is passive to the micronutrients, minerals such as calcium, iron, magnesium, copper and zinc, vitamins, especially vitamin E and other beneficial molecules and acids contained in the extracted oil, thereby contributing to the well being of one’s health. The visual and physical properties of the traditionally pressed oil are less attractive to refined oils. Further their stability and shelf life could be lesser as their processing does not involve use of preservatives, except palm sugar or jaggary, to enhance taste and color in a few types of oils. While the traditionally pressed oil preserves the good factor naturally available in the oil seeds, refined oil processing removes them through chemical processing.
Refinement of oil is carried out often by solvent extraction using hexane and oil seeds are processed at very high temperature ranges for expelling out oil. These two processing methods along with use of preservatives render the oil lifeless. The methods such as use of solvents to remove the stickiness of oil, making them free flowing and remove out beneficial fat contents to impart crystal clear solution of oil, adding preservatives to it thereby enhancing stability and shelf life render refined oil visually far better but compositionally poor in its beneficial aspects. The use of solvents and preservatives lead to generation of poly aromatic hydrocarbons that are proved to be carcinogenic in nature.
In traditional expeller machine oil seeds are crushed and pressed using wooden or stone pestles that help preserve the nutrients in the oil, despite considerable heat generation due to hard pressing that could affect its content to some extent but lesser than refining processes. The micronutrients and minerals present in the oil contribute to the bone strength and facilitate smooth movement of joints and acting against arthritis; the anti oxidants present in oil scavenge free radicals in the body thereby improving immunity.
Consideration of two value adding factors in traditional oil expelling process will be highly recommended to enhance its health benefits. First is minimizing heat generation at the time of oil seed pressing, by following through cold pressing methods thereby further preserving the nutritive constitution of the expelled oil. Second is use of organically grown oil seeds thereby avoiding residual effect of chemical pesticides and at the same time improve further on the nutritive value. These two value additions to the traditional pressed oil processing will be beneficial both to the producers and consumers of the product. That was clearely explained in world best Tamil News portal, Vikatan.