Canola oil is a vegetable oil derived from a variety of rapeseed that is low in erucic acid, as opposed to colza oil. There are both edible and industrial forms produced from the seed of any of several cultivars of the plant family Brassicaceae.
According to the Canola Council of Canada, an industry association, the official definition of canola is "Seeds of the genus Brassica (Brassica napus, Brassica rapa, or Brassica juncea) from which the oil shall contain less than 2% erucic acid in its fatty acid profile and the solid component shall contain less than 30 micromoles of any one or any mixture of 3-butenyl glucosinolate, 4-pentenyl glucosinolate, 2-hydroxy-3 butenyl glucosinolate, and 2-hydroxy- 4-pentenyl glucosinolate per gram of air-dry, oil-free solid." Canola oil is also used as a source of biodiesel.
The name for rapeseed comes from the Latin word rapum meaning turnip. Turnip, rutabaga (swede), cabbage, Brussels sprouts, and mustard are related to rapeseed. Rapeseed belongs to the genus Brassica. Brassica oilseed varieties are some of the oldest plants cultivated by humanity, with documentation of its use in India 4,000 years ago, and use in China and Japan 2,000 years ago.:55 Its use in Northern Europe for oil lamps is documented to the 13th century. Rapeseed oil extracts were first put on the market in 1956-1957 as food products, but these suffered from several unacceptable characteristics. Rapeseed oil had a distinctive taste and a disagreeable greenish color, due to the presence of chlorophyll. It also contained a high concentration of erucic acid.
Canola was bred from rapeseed cultivars of B. napus and B. rapa at the University of Manitoba, Canada, by Keith Downey and Baldur R. Stefansson in the early 1970s, having then a different nutritional profile than present-day oil in addition to much less erucic acid. Canola was originally a trademark name of the Rapeseed Association of Canada, and the name was a condensation of "Can" from Canada and "OLA " meaning "Oil, low acid", but is now a generic term for edible varieties of rapeseed oil in North America and Australasia. The change in name serves to distinguish it from natural rapeseed oil, which has much higher erucic acid content.
A genetically engineered rapeseed that is tolerant to herbicide was first introduced to Canada in 1995 (Roundup Ready canola). A genetically modified variety developed in 1998 is considered to be the most disease- and drought-resistant canola variety to date. In 2009, 90% of the Canadian crop was herbicide-tolerant. In 2005, 87% of the canola grown in the US was genetically modified. In 2011, out of the 31 million hectares of canola grown worldwide, 8.2 million (26%) were genetically modified.
A 2010 study conducted in North Dakota found glyphosate- or glufosinate-resistance transgenes in 80% of wild natural rapeseed plants, and a few plants that were resistant to both herbicides. This may reduce the effectiveness of the herbicide tolerance trait for weed control over time, as the weed species could also become tolerant to the herbicide. However, one of the researchers agrees that "feral populations could have become established after trucks carrying cultivated GM seeds spilled some of their load during transportation". She also notes that the GM canola results they found may have been biased as they only sampled along roadsides.
|Rapeseed oil production - 2014|
|Source: FAOSTAT of the United Nations|
In 2014, world production of rapeseed oil was 26 million tonnes, led by China, Germany, and Canada as leading producers accounting together for 47% of the world total. Canada was the world's largest exporter of rapeseed oil in 2016, exporting 2.9 million tonnes or approximately 94% of its total production.
In China, rapeseed meal is mostly used as a soil fertilizer rather than for animal feed, while canola is used mainly for frying food. In the words of one observer, "China has a vegetable oil supply shortage of 20 million tonnes per year. It covers a large percentage of that shortage with soybean imports from Brazil, the U.S. and Argentina."
There are several forms of genetic modification, such as herbicide (glyphosate and glufosinate, for example) tolerance and different qualities in canola oil. Regulation varies from country to country; for example, glyphosate-resistant canola has been approved in Australia, Canada, China, Japan, Korea, Mexico, Philippines, and the US, while Laurical, a product with a different oil composition, has been approved for growing only in Canada and the US.
In 2003, Australia's gene technology regulator approved the release of canola genetically modified to make it resistant to glufosinate ammonium, a herbicide. The introduction of the genetically modified crop to Australia generated considerable controversy. Canola is Australia's third biggest crop, and is used often by wheat farmers as a break crop to improve soil quality. As of 2008, the only genetically modified crops in Australia were canola, cotton, and carnations.
Genetically modified canola has become a point of controversy and contentious legal battles. In one high-profile case (Monsanto Canada Inc v Schmeiser) the Monsanto Company sued Percy Schmeiser for patent infringement after he replanted canola seed he had harvested from his field, which he discovered was contaminated with Monsanto's patented glyphosate-tolerant canola by spraying it with glyphosate, leaving only the resistant plants. The Canadian Supreme Court ruled that Percy was in violation of Monsanto's patent because he knowingly replanted the resistant seed that he had harvested and also imposing fees of over $200,000 on Schmeiser, but he was not required to pay Monsanto damages since he did not benefit financially from its presence.[dubious ] On 19 March 2008, Schmeiser and Monsanto Canada Inc. came to an out-of-court settlement whereby Monsanto would pay for the clean-up costs of the contamination, which came to a total of C$660. In Western Australia, in the Marsh v Baxter case, a GM canola farmer was sued by his organic neighbour because GM canola contamination led to the loss of organic certification. Although the facts of the case and the losses to the organic farmer were agreed between the parties, the judge did not find the GM farmer liable for the losses.
Europe has invested heavily in infrastructure to use canola oil for biodiesel, spurred by EU biodiesel policy initiatives.
Canola oil is made at a processing facility by slightly heating and then crushing the seed. Almost all commercial canola oil is then extracted using hexane solvent which is recovered at the end of processing. Finally, the canola oil is refined using water precipitation and organic acid to remove gums and free fatty acids, filtering to remove color, and deodorizing using steam distillation. The average density of canola oil is 0.92 g/mL (0.033 lb/cu in).
Cold-pressed and expeller-pressed canola oil are also produced on a more limited basis. About 44% of a seed is oil, with the remainder as a canola meal used for animal feed. About 23 kg (51 lb) of canola seed makes 10 L (2.64 US gal) of canola oil. Canola oil is a key ingredient in many foods. Its reputation as a healthy oil has created high demand in markets around the world, and overall it is the third-most widely consumed vegetable oil, after soybean oil and palm oil.
The oil has many non-food uses and, like soybean oil, is often used interchangeably with non-renewable petroleum-based oils in products, including industrial lubricants, biodiesel, candles, lipsticks, and newspaper inks, depending on the price on the spot market.
Some less-processed versions of rapeseed oil are used for flavor in some countries. Chinese rapeseed oil was originally extracted from the field mustard. In the 19th century, rapeseed (B. rapa) was introduced by European traders, and local farmers crossed the new plant with field mustard to produce semi-winter rapeseed. The accidentally similar genetic makeup in this cultivar to canola means the Chinese rape also contains lower levels of erucic acid. The flavor of the oil comes from a different production process: the seeds are toasted before being expeller-pressed, imparting a special flavor. In India, mustard oil is used in cooking. In the United Kingdom and Ireland, some chefs use a "cabbagey" rapeseed oil processed by cold-pressing. This cold process means that the oil has a low smoke point, and is therefore unsuitable for frying in Sichuan cuisine.
Canola oil is considered safe for human consumption, and has a relatively low amount of saturated fat, a substantial amount of monounsaturated fat, with roughly a 2:1 mono- to polyunsaturated fats ratio.
In 2006, canola oil was given a qualified health claim by the United States Food and Drug Administration for lowering the risk of coronary heart disease, resulting from its significant content of unsaturated fats; the allowed claim for food labels states:
"Limited and not conclusive scientific evidence suggests that eating about 1 ½ tablespoons (19 grams) of canola oil daily may reduce the risk of coronary heart disease due to the unsaturated fat content in canola oil. To achieve this possible benefit, canola oil is to replace a similar amount of saturated fat and not increase the total number of calories you eat in a day. One serving of this product contains [x] grams of canola oil."
A 2013 review, sponsored by the Canola Council of Canada and the U.S. Canola Association, concluded there was a substantial reduction in total cholesterol and low-density lipoprotein (LDL) cholesterol, and an increase in tocopherol levels and improved insulin sensitivity, compared with other sources of dietary fat. A 2014 review of health effects from consuming plant oils rich in alpha-linolenic acid, including canola, stated that there was moderate benefit for lower risk of cardiovascular diseases, bone fractures, and type-2 diabetes.
|Compound||Family||% of total|
|Alpha-linolenic acid||?-3||11% 9%|
|Saturated fatty acids||7%|
|Erucic acid||0.01% <0.1%|
Regarding individual components, canola oil is low in saturated fat and contains both omega-6 and omega-3 fatty acids in a ratio of 2:1. It is high in monounsaturated fats, which may decrease the risk of heart disease.
Although wild rapeseed oil contains significant amounts of erucic acid, the cultivars used to produce commercial, food-grade canola oil were bred to contain less than 2% erucic acid, an amount deemed not significant as a health risk. To date, no health effects have been associated with dietary consumption of erucic acid by humans; but tests of erucic acid metabolism in other species imply that higher levels may be detrimental.:646-657 Canola oil produced using genetically modified plants has also not been shown to explicitly produce adverse effects.
The erucic acid content in canola oil has been reduced over the years. In western Canada, a reduction occurred from the average content of 0.5% between 1987 and 1996 to a current content of 0.01% from 2008 to 2015. Other reports also show a content lower than 0.1% in Australia and Brazil.
|Almond oil||216 °C (421 °F)|
|Avocado||11.6||70.6||52-66||13.5||1||12.5||12.5:1||250 °C (482 °F)|
|Brazil nut||24.8||32.7||31.3||42.0||0.1||41.9||419:1||208 °C (406 °F)|
|Canola||7.4||63.3||61.8||28.1||9.1||18.6||2:1||238 °C (460 °F)|
|Cocoa butter oil|
|Coconut||82.5||6.3||6||1.7||175 °C (347 °F)|
|Corn||12.9||27.6||27.3||54.7||1||58||58:1||232 °C (450 °F)|
|Cottonseed||25.9||17.8||19||51.9||1||54||54:1||216 °C (420 °F)|
|Flaxseed/Linseed||9.0||18.4||18||67.8||53||13||0.2:1||107 °C (225 °F)|
|Grape seed||10.5||14.3||14.3||74.7||-||74.7||very high||216 °C (421 °F)|
|Hemp seed||7.0||9.0||9.0||82.0||22.0||54.0||2.5:1||166 °C (330 °F)|
|Olive||13.8||73.0||71.3||10.5||0.7||9.8||14:1||193 °C (380 °F)|
|Palm||49.3||37.0||40||9.3||0.2||9.1||45.5:1||235 °C (455 °F)|
|Peanut||20.3||48.1||46.5||31.5||0||31.4||very high||232 °C (450 °F)|
|Rice bran oil||232 °C (450 °F)|
|Safflower||7.5||75.2||75.2||12.8||0||12.8||very high||212 °C (414 °F)|
|Soybean||15.6||22.8||22.6||57.7||7||51||7.3:1||238 °C (460 °F)|
|Walnut oil||unrefined||9.1||22.8||22.2||63.3||10.4||52.9||5:1||160 °C (320 °F)|
|Sunflower (standard)||10.3||19.5||19.5||65.7||0||65.7||very high||227 °C (440 °F)|
|Sunflower (< 60% linoleic)||10.1||45.4||45.3||40.1||0.2||39.8||199:1|
|Sunflower (> 70% oleic)||9.9||83.7||82.6||3.8||0.2||3.6||18:1||232 °C (450 °F)|
|The nutritional values are expressed as percent (%) by mass of total fat.|