Cut use of re-heated oil at home, it may cause ailments
Despite considerable research pointing to the toxic effects of re-using edible oil deployed for frying purposes, the practice continues – in food outlets and homes
Despite considerable research pointing to the toxic effects of re-using edible oil deployed for frying purposes, the practice continues – in food outlets and homes. While commercial establishments follow the pernicious practice to cut costs, re-use of oil in homes comes from lack of consumer awareness.
Of course, unlike eateries, deep frying at homes is relatively for shorter periods because of the smaller quantities involved. In other words, the extent of deterioration in the quality and safety of the oil during deep frying in homes may not be as much as what one sees in commercial establishments, where the oil is heated and re-heated for long periods.
Yet, given the adverse effects of consumption of re-used oil on human health, it is imperative that households too take adequate steps to ensure the safety of the oil they use and thereby the food they consume. There’s another reason why consumers need to be educated on the adverse health effects of re-heated oil- many of them I spoke to, said they usually keep the oil used for frying separately and use it again for frying purposes only, as such oil does not lend itself to other foods- in terms of its flavour and taste! That’s certainly not a good practice.
A number of studies have linked repeated consumption of re-used oil to a variety of ailments such as hypertension, diabetes, cardiovascular and neurodegenerative diseases. A more recent study published in the Science Journal of Chemistry in 2019, also establishes a direct correlation between the length of heating and reheating of oil and the extent of damage to the organs. Here different groups of rats were fed with oil used for frying for varying times- four, eight , 12, 16, 20 and 24 hours. Even though all animals fed with re-used oil showed signs of liver injury, it was found that longer the exposure of the oil to high temperature, higher the damage to the liver. (“Effects of vegetable oil reused for frying on the liver of Albino rats”)
So how do you ensure the safety of the edible oil that you consume? Of course for food business operators, the food safety regulator has prohibited, under the Food Safety and standards (Prohibition and Restriction on Sales) Regulations, use of oil with a Total Polar Compounds of over 25 per cent. Obviously, households cannot check the oil for TPC.
Some nutritionists therefore advocate buying oils with a high smoke point for frying. Yet others say that oil should be chosen on the basis of its oxidative stability and not on its smoke point. Both groups give a list of oils that rank better for these qualities.
I think the best option is to (a) fry less and (b) use the minimum quantity that you would require to fry, so that by the time you complete the frying, very little oil is left and that can easily be discarded using an absorbent paper.
If you are reluctant to throw out the used oil, FSSAI suggests that you use keep it aside and use it for sautéing food, but not for frying again. And even here, the oil must be used within a day or two as the rate of deterioration of used oil is much faster.
FSSAI says that you must definitely get rid of used oil when blue-grey smoke appears or tough foam gets formed or oil becomes dark and murky or the consistency of oil changes. These are some of the indicators of deterioration in the quality of oil, says FSSAI.
Another important point to note is that oil should never be heated to such an extent that it starts smoking because it’s at that temperature that the oil really deteriorates.
So even while demanding stringent implantation of the FSS regulation on used oil for commercial establishments, consumers need to exercise restraint in terms of eating unhealthy, fried food - be it outside or at home. And I would include here packaged ‘namkeens’ or salty savouries too. And while on the topic, I would also urge celebrities not to promote or endorse such unhealthy foods.