Information AboutVegetable Oil |
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Vegetable oil or '''vegoil''' is Fat extracted from plant sources, known as oil plants. Although in principle other parts of plants may yield oil, in practice Seed s form the almost exclusive source. Vegetable oils are used as Cooking Oil s and for industrial uses. Some types, such as Cottonseed Oil , Castor Oil and some types of Rapeseed oil, are not fit for Human consumption without further processing. Like all fats, vegetable oils are Ester s of Glycerin and a varying blend of Fatty Acid s, and are insoluble in water but soluble in Organic Solvent s. SOURCES OF VEGETABLE OIL Common sources of vegetable oil include: Oilseeds:
Other vegetable oils:
See List Of Vegetable Oils for a more comprehensive list. According to the USDA , the total world consumption of major vegetable oils in 2000 was: Note that these figures include industrial and animal feed use. The majority of European rapeseed oil production is used to produce Biodiesel , or used directly as fuel in Diesel cars which may require modification to heat the oil to reduce its higher Viscosity . The suitability of the fuel should come as little surprise, as Rudolph Diesel originally designed his engine to run on Peanut Oil . See Also: Vegetable oil used as fuel EXTRACTION
Supercritical Carbon Dioxide can also be used for the extraction purpose and it is non toxic. {Link without Title} PRODUCTION Crude oil, straight from the crushing operation, is not considered edible in the case of most oilseeds. The same is true for the remaining meal. For instance, animals fed raw soy meal will waste away, even though soy meal is high in protein. Researchers at Central Soya discovered that a Trypsin Inhibitor in soybeans could be deactivated by toasting the meal, and both licensed their invention, and sold soy meal augmented with vitamins and minerals as MasterMix, a product for farmers to mix with their own grain to produce a high quality feed. The processing of soy oil is typical of that used with most vegetable oils. Crude soy oil is first mixed with caustic soda. Saponification turns free fatty acids into soap. The soap is removed with a Centrifuge . Neutralized dry soap stock (NDSS) is typically used in animal feed, more to get rid of it than because it is particularly nourishing. The remaining oil is deodorized by heating under a near-perfect Vacuum and Sparged with water. The condensate is further processed to become vitamin E food supplement, while the oil can be sold to manufacturers and consumers at this point. Some of the oil is further processed. By carefully filtering the oil at near-freezing temperatures, "winter oil" is produced. This oil is sold to manufacturers of salad dressings, so that the dressings do not turn cloudy when refrigerated. The oil may be partially Hydrogenated to produce various ingredient oils. Lightly hydrogenated oils have very similar physical characteristics to regular soy oil, but are more resistant to becoming rancid. Margarine oils need to be mostly solid at 90 degrees F so that the margarine does not melt in warm rooms, yet it needs to be completely liquid at 98 degrees F, so that it doesn't leave a "lardy" taste in the mouth. Another major use of soy oil is for fry oils. These oils require substantial hydrogenation to keep the polyunsaturates of soy oil from becoming rancid. Hardening vegetable oil is done by raising a blend of vegetable oil and a catalyst in near-vacuum to very high temperatures, and introducing hydrogen. This causes the carbon atoms of the oil to break double-bonds with other carbons, each carbon forming a new single-bond with a hydrogen atom. Adding these hydrogen atoms to the oil makes it more solid, raises the Smoke Point , and makes the oil more stable. Hydrogenated vegetable oils differ in two major ways from other oils which are equally saturated. During hydrogenation, it is easier for hydrogen to come into contact with the fatty acids on the end of the triglyceride, and less easy for them to come into contact with the center fatty acid. This makes the resulting fat more brittle than a tropical oil; soy margarines are less "spreadable". The other difference is that trans fatty acids are formed in the hydrogenation reactor. Trans acids are increasingly thought to be unhealthful. HISTORY OF VEGETABLE OILS IN THE UNITED STATES While olive oil and other pressed oils have been around for millennia, Procter & Gamble researchers were innovators when they started selling cottonseed oil as a creamed shortening, in 1911. Ginning Mill s were happy to have someone haul away the cotton seeds. P&G researchers learned how to extract the oil, refine it, partially hydrogenate it (causing it to be solid at room temperature and thus mimic natural lard), and can it under nitrogen gas. Compared to the rendered lard P&G was already selling to consumers, Crisco was cheaper, easier to stir into a recipe, and could be stored at room temperature for two years without turning rancid. (P&G sold their fats and oils brands - Jif and Crisco - to The J.M. Smucker Co. in 2002.) Soybeans were an exciting new crop from China in the 1930s. Soy was protein-rich, and the light tasteless oil was extremely high in polyunsaturates. Henry Ford established a soybean research laboratory, developed soybean plastics and a soy-based synthetic wool, and built a car ''almost entirely'' out of soybeans. Roger Drackett had a successful new product with Windex , but he invested heavily in soybean research, seeing it as a smart investment. By the 1950s and 1960s, soybean oil had became the most popular vegetable oil in the US. In the mid-1970s, Canadian researchers developed a low-ecruic rapeseed cultivar. Because the word "rape" was not considered optimal for marketing, they coined the name "canola" (from "Canada Oil"). The fats than other popular oils. Canola is very thin (unlike corn oil) and flavorless (unlike olive oil) so it largely succeeds by displacing soy oil, just as soy oil largely succeeded by displacing cottonseed oil. INDUSTRIAL USES
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