Vegetable oils toxic? Some new findings are spawning a debate

Frying, using edible oils, is one of the most practiced food preparation methods as it gives characteristic aroma, texture and taste that is unmatched compared to other processes. Baking, also requiring specialty fats, is another process that can give hundreds of products, universally liked, though it needs high temperature heating equipment and industrially, bakery industry many be one of the biggest in food processing sector creating a variety of products like bread, biscuits, pastries etc. While baking is based more or less on wheat and its unique protein Gluten, frying has the advantage of using any raw material including cereals, pulses, vegetables, fruits, meat, fish and their combinations. Frying needs an oil which requires to be heated to temperatures varying from 160 C to 200 C for a few minutes to attain the desirable color and texture depending on the input material. Organoleptically fried food can be quite appealing and often addictive and health and nutrition experts always caution against its regular consumption that too in larger quantities because of its contribution to the obesity epidemic that is becoming a scourge in most countries causing diseases like diabetes, cardiac malfunctioning, hypertension and a host of others. Experts agree that calories derived from fat, both direct and indirect, should not exceed 30% of the total calories consumed in a typically normal diet working out to about an upper limit of 50 gm daily per capita.

While in the organized fried food manufacturing sector big capacity continuous fryers are used containing high volume of the frying oil, small and unorganized players use batch fryers with or without any temperature control. But invariably the oil is subjected to continuous heating for getting large quantities of products for supplying to the market. In house holds however the fryers, mostly shallow stainless steel pans, are used once or twice a week though the oil is repeatedly reused after each frying operation with occasional topping up. Usually frying oils are rarely thrown away unless it becomes too dark or sticky. There is no unanimity among scientists whether continuous heating does more damage than intermittent heating but all tend to agree that there will be heat damage to the oil to varying extent, depending on the chemical nature of the one used. More the degree of unsaturation in the fatty acid molecules higher will be the extent of damage. Higher temperatures and longer duration of frying can cause extensive damage, decomposition and interaction among the artifacts generated.

What will be the implications of damage to the oil, besides developing flavor problems to the products fried repeatedly in such oils? A matter of much concern is the effects of such oil damage to the human health. Till recently, frying industry was more concerned about oil damage because of loss of quality in the product besides economic losses incurred due to discarding of precious oil once it fails to meet the mandatory standards after repeated and long duration heating. As edible oils are made of organic chemical substances, mainly fatty triglycerides, they have their typical smoke point and flash point in terms of characteristic temperatures beyond which they decompose rapidly into hundreds of artifacts some of which are considered injurious to health. Among them aldehydic lipid oxidation products are considered highly hazardous to humans whether they are inhaled or consumed orally through foods. If so, those using oils vulnerable to generate toxic aldehydes during frying can be dangerous to both consumers as well as to the workers involved in the factories as the latter is exposed to volatile aldehydes continuously during the manufacturing operations.  .          

Toxic aldehydes like 4-hydroxy-(E)2 nonenal, 4-oxo-(E)-2 decenal and 4-oxo-(E)-undecenal, derived from alpha, beta unsaturated fats have been linked to many types of cancer and neurodegenerative diseases like Alzheimer's and Parkinson;s. These aldehydes, being highly reactive can combines with tissue proteins, enzymes and hormones affecting the functioning of many organs in the human body. It is because of this reason that fried foods made from oils with high amounts of alpha, beta poly unsaturated fatty acids are fraught with high risks for human consumption. According to available data which are rather limited in this area of concern, some of the frying oils found to be relatively safe are coconut oil, virgin olive oil, butter, lard and palm oil all of which contain predominantly saturated fatty acid triglycerides. It is interesting that oil derived from sunflower seeds happened to the worst performer, mostly attributed to the presence of more than 82% of unsaturated fatty acid triglycerides yielding toxic aldehydes at levels much higher than that recommended by the WHO to be safe.   

According to some findings by scientists, a typical meal of fish and chips fried in vegetable oils contained 100 to 200 times more toxic aldehydes than the safe limit set by the WHO and the consumption such products regularly can lead to serious consequences to the brain functions in the long term. Some even compare such disastrous changes in human brains to the adverse climate changes the world is facing to day. How far such comparisons are realistic is a matter of debate though it definitely raises alarm among health experts who feel that more intense studies are required to be undertaken to unravel the mysteries of toxic aldehydes. One is troubled by the report that Sunflower oil is the oil targeted in these studies and the rationale is that it contains high levels of unsaturated fatty acids (UFAs), to the extent of 91%. If so what about oils like olive oil which is found to be a safe cooking oil though it contains 84% unsaturated fatty acids. How about other oils like mustardc oil (81% UFA), or peanut oil (82% UFA) ? Here again does the nature of UFA make any difference in generating toxic aldehydes during heating? No one knows for sure whether extent of MUFA or PUFA  or their ratio in these oils determine the dynamics of toxic aldehyde formation. Also not clear is whether unprocessed vegetable oils containing many natural antioxidants and bioactive phytochemicals can generate toxic substances on being used as frying oils. A note worthy fact in the Olive oil experiment is that the scientists used virgin olive oil which is valued very much for its unique flavor profile to say it is a good frying oil which again raises the question regarding the role of natural antioxidants present in virgin oil compared to its processed counterpart.

While earlier studies used simulating experiments and model systems to find out the formation of toxic chemicals in frying oil at high temperatures for duration as long as 20-40 hours, some recent studies confirmed that even a few minutes exposure to frying temperatures would be sufficient to create sufficient levels of toxic chemicals when oils like Sunflower oil is used. A logical question that arises out of these studies is the influence of antioxidants and other oil protectants like scavengers of polar compounds added to frying oils by the processing industry on generation of toxic substances. Unfortunately no data seem to be existing to verify this crucial issue. On the face of it the recommendation that coconut oil is the best frying oil may be note worthy, especially when frying is done in households or restaurants using non stabilized frying oils. Also to be borne in mind is that unless more emphatic studies by divergent group of lipid scientists confirm these stray findings, all vegetable oils should not be condemned as unsafe for frying.

V.H.POTTY
http://vhpotty.blogspot.com
http://foodtechupdates.blogspot.com

Life is precious-Why do people give it up?

Life is considered a precious gift from God by most people in the world though there are a few atheists who think there is nothing like a God. However as long as man is not able to revive a completely dead person back to normal life or create artificial life one has to admit the existence of an omnipotent force with powers beyond what human beings, in spite of vast scientific and technological prowess at their disposal, possess. There are occasional reports that some scientists are on the threshold of creating artificial life though it cannot be still considered satisfactory to sideline God yet. Probably in years to come man may succeed but one has to wait for that day before casting serious doubt about the existence of God. This is a controversial issue and people on both sides of the divide will have to respect each others' feelings.

If life is a precious thing why do people commit suicide so often knowing pretty well that they can never return back to life? One of the most accepted views is that suicide happens when the extreme mental condition of the person does not allow him to think seriously the mind boggling consequences of committing such an act and in many cases those who fail in their effort to take their life in the first attempt invariably give up unless there is serious mental derangement. According to WHO experts on a global basis, one suicide takes place every 40 seconds working out to an annual suicide rate of 8 lakh per year. It is interesting to see that suicide rate varies from country to country though low income and middle income countries report higher suicide rates. Thus no one country is immune to suicidal tendency whether rich or poor, whether in Asia, America, Africa or Europe. Another notable phenomenon is that those who choose death voluntarily are mostly illiterates! 

India is a country where suicide rates are considered high though there are others with almost double the rate in other continents. If one believes in the babu version of government of India there were only 134, 600 deaths due to suicide in India in the year 2012 but WHO where such deaths are systematically documented the real figure was 258, 075 out of which 99, 977 were women and 158, 098 men. Obviously there must be some suppression of data in India or the documentation system is faulty. Overall there is 21.1 suicides for every 1 lakh population. It is not a consolation that a poor country like Guyana has a suicide rate as high as 44.2 per one lakh population or for that matter Sri Lanka recorded 28.8 deaths or Nepal had a figure of 24.9 suicides per one lakh. What is appalling is that in Indian suicide rate is high when it comes to the age group of 15-29 years aggregating to 35.5 per lakh while among 30 to 49 years group the rate falls to 28 per lakh. 

Suicide by farmers is always sensational and the media loves to report them promptly accusing the governments for such happenings in the country. However farmer suicides are less than 10% of the national figure though self inflicted deaths in rural belt is mostly due to serious financial indebtedness and insurmountable difficulties to meet both the ends meet on account of drought and crop failure. Pesticide poisoning, hanging and self immolation account for most deaths in countries like India while firearms are extensively used in countries like the US where they are easily available in the market. Interestingly in most wealthy countries poverty or hunger is not the primary reason for self-inflicted death but it is the acute mental disorders that drive them to this extreme step. Koreans are an interesting case where suicide rates are as high as 28.9 to 38.5 per lakh. Though on the development scale South Koreans are far ahead with high per capita income, the suicide figure tells a different story. There the figure is almost 29 per lakh while in North Korea it is 38.5 per lakh. 

What about our neighbor China? It is a confusing picture there as there are no independent reports that can substantiate the official claims by the government, The claim that it has dramatically reduced suicide rate from 22.3 per lakh a decade ago to 9.8 per lakh, a reduction of about 58% cannot be verified but even if if it is partially true the achievement is really noteworthy. One of the reasons attributed to this phenomenon is the rapid, conscious and massive urbanization programs initiated by the communist government and many social welfare supports available to the citizens. This is understandable because suicides take place mostly in rural and semi-urban areas for which no credible explanation is still available.    

In absolute numbers maximum suicides take place in India, about 2.6 lakh out of a global figure of 8 lakh (almost 33%) though country's population is less than 18% of world population. This may prompt critics to call India the suicide capital of the world. It is a poor reflection on the metal strength of the nation which boasts of 5000 years of glorious history, an ancient civilization and the epicenter of epics like Mahabharata and Ramayana,  In a land where Buddha and Mahavir Jain were born, peace within and around should have been a strong trait among their descendants. Also this is the land where Mahatma Gandhi, the Universal Apostle of nonviolence was born and attained martyrdom. If so why this depredation, deprivation, desperation and predisposition that drive people to destroy their own lives? Where has this country gone wrong in evolving such a destructive environment when people think of taking their own lives? Is there a spiritual bankruptcy or lack of self confidence or a sense of helplessness which is responsible for this situation? There is an urgent need for introspection among Indians vis-a-vis the factors that drive some of their fellow citizens towards self destruction so as to bring about radical self corrective measures.

   

V.H.POTTY

http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com