Uses of hydrogenated oils

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Hydrogenated oil is produced by the process of hydrogenation. Hydrogenation is the process in which we force hydrogen gas into oil at high pressure and temperature. It is the oil in which the essential fatty acids have been converted to a different form chemically, which has several effects. Hydrogenated oil is far more shelf stable, and will not go rancid as quickly as untreated oil. When hydrogenated, the chemical structure of the oil is changed. It also has a higher melting point.

Hydrogenation is the chemical reaction that results from the addition of hydrogen (H2). The process is usually employed to reduce or saturate organic compounds. The process typically constitutes the addition of pairs of hydrogen atoms to a molecule. Catalysts are required for the reaction to be usable; non-catalytic hydrogenation takes place only at very high temperatures. Hydrogen adds to double and triple bonds in hydrocarbons.


It is manufactured through following processes-

  1. Preparation of seeds begins with heating and dehulling, followed by chopping or grinding, to break the cell walls, freeing the oil to make the penetration of solvents into the cells easier. This is accomplished by rolling or flaking, but it is still not enough to release all of the oil. Therefore, a thermal or conditioning step is required. In addition, all oil seeds have enzymes that can influence quality. During processing, the object is to deactivate these enzymes early by means of heat. For example, with canola or rapeseed, the enzyme myrosinase can influence quality because it catalyses hydrolysis of glucosinolates to give glucose, sulphate, isothiocyanates, oxazolinine thiones, and other compounds. Some of these compounds act as a catalyst poison during hydrogenation of oil for margarine production.
  2. Extraction from seeds is accomplished either by mechanically pressing or by mixing with such gasoline-like solvents as hexane and heptane (which are lung irritants and nerve depressants). At this stage, if the chemical extraction method is used, the oil is extremely flammable, and some factories have been known to blow up or catch on fire. Later, the oils are steam heated to evaporate the solvents at temperatures around 300°F. Most of the solvents are evaporated, but not all. The primary objective of this step is to produce a clean, crude oil product. Be aware that, at this stage, the oil can now be bottled and sold as "unrefined oil" in health food stores and delicatessens. Oil designated for more refining goes through more processing procedures. After being mashed and cooked for up to two hours at varying temperatures, depending on the seed type, mechanically pressed seeds are subject to additional heating during the "auger" process, where the average temperature reaches about 120°C (248°F) with higher temperatures and pressures producing more oil. At this temperature, however, oil reacts with oxygen more than 100 times faster than at room temperature, producing fatty acid damage. In some cases, after mechanical pressing, the oil is filtered and sold as unrefined oil, but more often, the oil undergoes further refining.
  3. Degumming is a treatment of crude oils and water, salt solutions, dilute acids, or alkalis used in order to remove phosphates, waxes, and other impurities. Caustic soda, (often sodium hydroxide -- commonly known as Drano -- or a mixture of sodium hydroxide and sodium carbonate) is one such substance used to remove free fatty acids that can cause rancidity and decreases the quality of the oil. Alkali solutions combine with the free fatty acids to form soaps and also helps to remove toxic substances that are naturally present in many plants. Temperatures again have reached 75°C (167°F). At this stage, the oil still has its pigmentation of red, yellow, or greenish hue, which is also deemed undesireable. Degumming converts the phosphatides to hydrated gums which are insoluble in oil and readily separated as sludge. The hydrated gums are vacuum dried for crude lecithin processing. This process also involves the addition of phosphoric acid and water at temperatures of 60°C (140°F).
  4. The industry's rationale for the degumming process is as follows:

    • It is necessary to remove the lecithin, which can cause rancidity of the oil.
    • It satisfies export oil requirements for a product free of impurities that settle out during shipment.
    • Gum removal prior to alkali refining often improves yield because the phosphates can act as emulsifiers in a caustic solution, increasing the neutral oil contained in the soapstock.
    • It substantially decreases refinery waste load because of the lower neutral oil losses and the reduction of gums discharged.
    • It prepares the oil for steam refining. Degummed oil is more suitable to this physical refining technique because of the significant reduction in such nonvolatile impurities as phosphatides and metallic prooxidants.
    • It results in improved acidulation performance. The soapstock from alkali refining is easier to acidulate because of lower emulsifier content, and the acid water has less impact on the wastewater treatment systems.
  5. Bleaching oils is necessary because they have a strong yellow or reddish pigment that is considered undesirable. In the bleaching process, oils are heated to temperatures of 175°-225°C, for about 4 hours, and mixed with a type of clay substance that will absorb the unwanted pigment. Most of the spent clay is then filtered from the oil. During this phase, some of the polyunsaturated fatty acids may undergo oxidation and toxic peroxides, forming conjugated fatty acids.
  6. Deoderization is done through pressurized steam distillation at temperatures of 240°-270°C for 30 to 60 minutes, which removes undesirable odors and tastes from the oil. Note: When temperatures go above 150°C , unsaturated fatty acids become mutagenic. Above 160°C, trans fatty acids begin to form. Above 200°C , trans fatty acids multiply substantially, and, above 220°C, the rate of trans fatty acids explodes. Deoderizing reduces the content of many other substances, including residues, toxins, and products of oxidation formed during the bleaching stage, as well as removing sulphur, monoglycerides, sterols, beta carotene, and tocopherols (Vitamin E). The oil is now tasteless and cannot be distinguished from other oils derived from seeds or plants. At this point, despite all of the heating involved, the oils can still be sold as "cold-pressed" since there is no accepted definition of the term. Preservatives are added such as synthetic antioxidants, BHT (butylated hydroxytoluene), BHA (butylated hydroxyanisole, propyl gallate, TBHQ (teriary butyhydroquinone), citric acid, or methylsilicone. A defoamer may also be added to prevent turbidity when refrigerated.
  7. Hydrogenation: After all this, oils not designated for sale, go on to more processing in the form of hydrogenation to make margarines, shortenings, and shortening oils. The hydrogenation of oils converts liquid oils into hard fats by adding hydrogen to the fat molecule. Oils can be hydrogenated to varying degrees, depending on the hardness. The most common forms are shortening, margarines, and the partially hydrogenated fats used for frying and in processed foods. These fats are desirable for its melting point, allowing for high temperature cooking and frying. Hydrogenation involves the artificial saturation of fully refined oils to harden them into spreadable products. All oils sold in supermarkets and convenience stores are processed in the above manner. "ALL" includes safflower, walnut, sunflower, corn, grape seed, soybean, sesame, rice bran, canola, almond, peanut, avocado, and others including blends. Olive oil is the only oil sold on supermarket shelves that is not heated above 150°C.

After the refining process above, oils are put under pressure, using hydrogen gas at temperatures of 120-210°C (248-410°F) in the presence of a metal catalyst (nickel, platinum, or copper) for six to eight hours. A nickel catalyst is actually 50% nickel and 50% aluminum. Remnants of both metals remain in the final products of hydrogenated or partially hydrogenated goods. During complete hydrogenation, all double bonds are saturated with hydrogen. This means there are no unsaturated fatty acids, no w6's, and no w3's. In some partially hydrogenated margarines, the trans fatty acid content can be more than 60%. Partially hydrogenated oils are found in French fries (37.4%), candies (38.6%), and bakery products (33.5%). A completely hydrogenated oil is now a hard fat containing no essential fatty acid activity, causing a nation-wide deficiency of the essential fatty acids.

COLD PRESSED OILS: "Cold pressed" is a term used to describe oils that have been mechanically pressed slowly so that temperatures do not rise above 140°F -- technically speaking. However, it is actually a term searching for a meaning since there are no firm regulations regarding it. Manufacturers claim that if no external heat is applied, the oil qualifies as "cold-pressed," yet these oils can be processed by the same methods as supermarket oils. As seen in the processing method, "cold-pressed" is not an accurate depiction of reality since temperatures can reach well above the minimum "standard" without "external" heat being applied. Machines heat up during mechanical pressing. In Switzerland, cold pressed is defined as those oils which have not exceeded temperatures of 50°C from seed to bottle. In North America, there is no such specification. Oils sold as "cold pressed" can be labelled as "unrefined," "unprocessed," "expeller-pressed," etc., and sold in dark containers just like cold-pressed oils that have maintained high quality standards. The secret is in knowing the source and how they produce their oil. A terms to watch for here is "completely protected from light and air during processing" because essential fatty acids absorb sunlight increasing their ability to react with oxygen more than 1000 times opening the door for them to spoil faster, causing free radicals.

Cold pressed oils are more intense in taste and color than refined oils, containing 25-50% more Vitamin E, 45% more beta-sitosterols, and significantly lower levels of trans-fatty acids than refined oils. Unrefining also preserves the essential fatty acids. These oils are usually made from organic seeds since non-organic seeds contain high levels of pesticide residues, which are only partially removed from refined oils The reliable cold-pressed oils are usually sold in health food stores and are to be kept refrigerated.

According to Udo Erasmus, the ideal oil produced should have these steps in mind:

  • Machine parts are made of special metals, avoiding copper, brass, and iron, which catalyze oil breakdown. These metals should not be used in pipe lines or tanks either.
  • Containers should be made of black polyethylene to completely block out light and ultra violet light.
  • Oil is extracted by gravity rather than filters.
  • All containers and lines are flushed with inert gas to clear oxygen.
  • Tin and solder should be rejected since they contain lead.

Labelling trans fatty acids is a nightmare, varying from country to country. In the US, trans fatty acids are lumped together with monosaturated fats with no differentiating between the health-supporting group and the damaging group. Since monosaturated fats are considered a healthy choice, consumers are unaware that they are consuming harmful trans fats along with the healthy monosaturated ones. Trans fatty acids are largely a product of commercial processing called "hydrogenation." This type of fatty acid raises total cholesterol including LDL ("bad" cholesterol) while reducing HDL ("good" cholesterol). This is particularly noted in the French, who consume just as much of the saturated fats as North Americans, but use butter, olive oil, and other vegetable oils for cooking, whereas the majority of the North American diet consists of other types of harmful fats.


This is used in shortenings for deep frying in restaurants, as they can be used for longer than most conventional oils before becoming rancid. In the early twenty first century non-hydrogenated vegetable oils became available that have lifespans exceeding that of the frying shortenings. As fast food chains routinely use different fats in different locations, trans fat levels in fast food can have large variations. For example, an analysis of samples of McDonald's French fries collected in 2004 and 2005 found that fries served in New York City contained twice as much Trans fat as in Hungary, and 28 times as much as in Denmark (where trans fats are restricted). At KFC, the pattern was reversed with Hungary's product containing twice the trans fat of the New York product. Even within the US there was variation, with fries in New York containing 30% more trans fat than those from Atlanta.


Hydrogenated oil is oil that has been molecularly altered through the process of hydrogenation. During hydrogenation, hydrogenation gas is fused into heated oils and attached to fatty acids. The process of hydrogenation removes all of the "good" out of the oil (essential fatty acids like Omega 3s) and makes the fat completely toxic to the body. The hydrogenation gas is fused into the oils using a metal catalyst like aluminum ,nickel, and cobalt- all 3 are metals that are toxic to the body. The body does not recognize the new molecular structure of the oil (which now closely resembles the chemical make up of stearic acid, used to make candles) and cannot break it down.

What happens when you eat hydrogenated oils?

Just how bad is this ingredient for your health? Consider this list of detrimental health effects caused by hydrogenated oils, published in a report:

  • Directly promotes heart disease
  • Promotes cancers: breast cancer, prostate cancer, colon cancer
  • Results in low birth weight infants
  • Raises LDL (bad) cholesterol and lower HDL (good) cholesterol
  • Raises blood sugar levels and promotes weight gain
  • Interferes with the absorption of essential fatty acids and DHA
  • Impairs brain function and damages brain cells
  • Accelerates tumor growth
  • Accelerates the progress of type-2 diabetes
  • Raises serum cholesterol
  • Impairs immune system function
  • Promotes attention deficit hyperactivity disorder (ADHD)
  • Impairs development of the brains of fetuses
  • Causes gallbladder disease
  • Causes liver disease
  • Causes 30,000 deaths per year in the United States alone
  • Clogs blood, makes blood cells stick together
  • Blocks the body's creation of natural pain-reducing hormones (eicosanoids)
  • Causes the creation of free radicals that promote inflammation
  • Creates nutritional deficiencies of healthy oils and essential fatty acids (EFAs)
  • Promotes cystic fibrosis
  • Lowers essential fatty acids in the breast milk of nursing mothers
  • Clogs artery walls and promotes atherosclerosis
  • Cause gum disease and rotted teeth
  • Lowers tissue oxygen intake
  • Causes infertility
  • Directly damages blood vessels
  • Causes high blood pressure
  • Weaken cell walls and compromises cellular structure
  • Causes dandruff and acne

Tips to Avoid Hydrogenated Oils

  1. To help avoid hydrogenated oils, most of your foods should be raw and as close to their natural state as possible. This means more fruits and vegetables including organic local meats as fresh as possible. The more real foods from nature that you eat, the less packaged and processed foods you'll consume. It's the packaged and processed foods that are most likely to be made with hydrogenated oils to help increase their shelf life.
  2. This really means a change in the way that we think about food and what we classify as food. True foods are those from nature, in their natural pristine state, not those that come out of a factory or a box. You can't rely on the government or any other source to tell you what is ok to put into you or your families body.
  3. It absolutely means becoming a label reader and checking everything you buy that's packaged and processed. You especially want to make sure that hydrogenated oils and other negative ingredients such as high fructose corn syrup are not listed as ingredients, even on packages that have the word "organic" on the box.
  4. Just because a package has the word organic on the label doesn't mean that it's necessarily a healthy food. Packaged and processed foods with organic on the box would really be considered "less damaging" but not truly healthy. To be truly healthy means that a food is full of enzymes, phytonutrients, and life force with all their natural vitamins and minerals present.
  5. Enzymes are actually more important than any vitamin, mineral or other nutrient since all processes that occur in the body must have sufficient supplies of enzymes to do their job. Foods that have had their enzymes destroyed are automatically classified as "dead foods"
  6. Hydrogenated oils are absolutely one of the worst ingredients being put into the modern food supply today for the many reasons stated. This is an ingredient that must betotallyavoided at all costs. This is especially important if you're looking to recover your health in any form.
  7. Beware that eating out in restaurants can pose just as great a health risk as packaged and processed foods do. That's because many restaurants use hydrogenated oils in nearly everything they prepare. This is another reason that eating out too often can have very negative health effects.

The best solution is to prepare your own foods at home as often as you can and getting as far away from a processed food diet as possible. This way you know exactly what you're putting into your body and not leaving it up to modern manufacturers of today's so called "foods" that have no concern for your health or well being at all.