What is a vegetable oil? Any form of lipid that is obtained from plants which exists in liquid form at room temperature is automatically classified as a vegetable oil. In contrast to that, it will be called a vegetable fat if it is in its solid form at room temperature. This essentially means that there are many different types of vegetable oils, each coming from different plants. Most oils contain triglycerides which are the basic component of most lipids and can store a large amount of energy compared to sugars, which is what makes oils fattening. Although they basically have the same structure, each type of oil is functionally and distinctly different from one another.
A few examples of the most commonly used vegetable oils are the olive oil, the coconut oil and the almond oil. These oils have been used since the dawn of civilization by ancient tribes for a variety of purposes, with the earliest documentation of such use dating back all the way to 4000 years ago. Most of the oils back then were used for medicinal purposes because of their powerful health benefits.
One downside of all vegetable oils is that they cannot be stored for extended periods of time because they will turn rancid, causing an unpleasant odour or smell. This happens because they chemically react with atmospheric oxygen, but this process can be slowed down by reducing its exposure to air. Different types of oil react with oxygen at varying degrees and are measured by something called oxidative stability.
These oils are extracted using a wide variety of ways, ranging from a process called fractional distillation (commonly used in the purification of crude oil) to the more traditional “crushing” method from parts of the constituent plant. Most of the oils are extracted from the seeds of the plant, while a small minority are extracted from other parts like the roots or stem. Some vegetable oils are inherently more expensive than the others because of the costly nature of the extraction process and also the difficulty to cultivate the particular plant. Be warned that not all vegetable oils are suitable for consumption as some are non-digestible. The inedible ones are used for other industrial purposes whereas the edible ones are mostly used as cooking oils.
Inedible Vegetable Oil
Believe it or not, a lot of products that we use daily today contain some form of vegetable oil added into it. This is especially true for products like perfumes, paints and shampoos. Other products like lubricants are usually purely comprised of inedible vegetable oils with some additives added. In perfumes, certain vegetable oils are added as a fragrance because of their strong scent. In paints, they help to speed up the drying process and they are used because of their medicinal properties in shampoos. These are only a few examples of what unique things these oils can do for us.
Edible Vegetable Oil
On the other hand, edible oils play a major role in the culinary industry as stated above. Their most common use would be to heat and cook food, but is also regularly used to add flavour or texture to the food. Seed oils like sesame oils are commonly used for these purposes.
Animal Oil Versus Vegetable Oil
There has been growing controversy about which oil is healthier for consumption. Animal oils are primarily made up of saturated fats (or saturated triglycerides) whereas vegetable oils are made up of unsaturated fats (polyunsaturated or monounsaturated). The growing amount of evidence today suggests that animal oils are unhealthy if taken in regularly.
They are thought to cause various cardiovascular diseases and may lead to an increased risk of heart attacks or strokes and in extreme cases, even cancer. This is because regular consumption of saturated fats leads to higher levels of low-density lipoproteins, also known as bad cholesterol in the blood system. This increased level of LDLs can clog arteries and cause serious, adverse effects on the cardiovascular system.
A long, verbose explanation of the controversial vegetable oil
However, some vegetable oils can cause even more harm to your health than animal oils. These are the hydrogenated vegetable oils. Hydrogenated vegetable oils are oils in which hydrogen have been artificially added into them to make them more stable by resisting oxidation (turning rancid) and so prolonging their shelf life or to change their physical state from liquid to solid.
A profound example would be the margarine which is completely made up of hydrogenated oils. This is what helps make it possible for it to exist as a solid state at room temperature. In fact, these hydrogenated oils are so harmful to health that at one point in time, substances like margarine were completely banned in countries like Canada and the United States. Therefore hydrogenation of these oils offers no real benefit and is for industrial purposes only. It has zero nutritional value and you should avoid consuming it altogether.
Artificially hydrogenated vegetable oils contain large amounts of trans fats, especially if they are only partially hydrogenated. These trans fats, like saturated fats, also help increase the risk of heart attacks and various cardiovascular diseases but at a faster rate. They do this by both increasing levels of low-density lipoproteins and decreasing levels of high-density lipoproteins (the good cholesterol) in our body. HDLs help prevent clogs in arteries and a high level of it in humans is linked to a lower mortality rate. A reduced amount of HDLs caused by trans fats from hydrogenated oils help catalyse the formation of plaques in arteries, potentially blocking a major blood vessel such as the coronary artery.
Most health experts today agree that consuming unprocessed or naturally occurring oils which are not hydrogenated are healthier than their processed counterparts. These unprocessed oils, although polyunsaturated, contain less amounts of trans fat in them and have been proven by several studies to significantly lower the risk of a heart attack and the occurrence of breast cancer in women by a whopping 20%.
Constantly consuming food that is only cooked using unprocessed oil does not ultimately mean a healthier lifestyle. Carefully balance your diet by consuming little saturated fats and avoiding artificially hydrogenated oils altogether. If you want to watch your weight, it is best to avoid oily food and reduce intake of all types of oil.
Vegetable Oil As Biofuels
Their use as biofuels is becoming increasingly important today as our supply of fossil fuels diminish by the second. They are generally cheaper than conventional fossil fuels but supply almost as much energy. Unlike fossil fuels, biofuels can be mass-produced and will never run out as long as we continue to grow their constituent plants. They make engines more efficient and help them run more quietly. Most importantly, they help reduce the amount of pollutants and greenhouse gases commonly released by conventional fuels.