Canola is one of two cultivars of rapeseed or Brassica campestris (Brassica napus L. and B. campestris L.).[1] Their seeds are used to produce edible oil that is fit for human consumption because it has lower levels of erucic acid than traditional rapeseed oils and to produce livestock feed because it has reduced levels of the toxic glucosinolates.[2] Canola was originally naturally bred from rapeseed in Canada by Keith Downey and Baldur R. Stefansson in the early 1970s,[3][4] but it has a very different nutritional profile in addition to much less erucic acid.[5] The name "canola" was derived from "Canadian oil, low acid" in 1978.[6][7] A product known as LEAR (for low erucic acid rapeseed) derived from cross-breeding of multiple lines of Brassica juncea is also referred to as canola oil and is considered safe for consumption.[8]
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Canola oil is made at a processing facility by crushing the rapeseed. Approximately 42% of a seed is oil. What remains is rapeseed meal, a high quality animal feed. 50 pounds of rapeseed makes approximately 10 litres of canola oil.
Canola is a key ingredient in many of the foods we eat. Its reputation as a healthy oil has created high demand in markets around the world. Canola oil has many non-food uses, and often replaces non-renewable resources in products including candles, lipsticks, newspaper inks, industrial lubricants and biofuels.
Once considered a specialty crop in Canada, canola has become a major North American cash crop. Canada and the United States produce between 7 and 10 million tonnes of canola seed per year. Annual Canadian exports total 3 to 4 million tonnes of the seed, 800,000 tonnes of canola oil and 1 million tonnes of canola meal. The United States is a net consumer of canola oil. The major customers of canola seed are Japan, Mexico, China and Pakistan, while the bulk of canola oil and meal goes to the United States, with smaller amounts shipped to Mexico, China, and Europe. World production of rapeseed oil in the 2002–2003 season was about 14 million metric tons.[9]
Canola was developed through conventional plant breeding from rapeseed, an oilseed plant already used in ancient civilization. The word "rape" in rapeseed comes from the Latin word "rapum," meaning turnip. Turnip, rutabaga, cabbage, Brussels sprouts, mustard and many other vegetables are related to the two canola varieties commonly grown, which are cultivars of Brassica napus and Brassica rapa. The negative associations due to the homophone "rape" resulted in creation of the more marketing-friendly name "Canola". The change in name also serves to distinguish it from regular rapeseed oil, which has much higher erucic acid content.
Hundreds of years ago, Asians and Europeans used rapeseed oil in lamps. The Chinese and Indians used a form of canola oil that was unrefined (natural).[10] As time progressed, people employed it as a cooking oil and added it to foods. Its use was limited until the development of steam power, when machinists found rapeseed oil clung to water- or steam-washed metal surfaces better than other lubricants. World War II saw high demand for the oil as a lubricant for the rapidly increasing number of steam engines in naval and merchant ships. When the war blocked European and Asian sources of rapeseed oil, a critical shortage developed and Canada began to expand its limited rapeseed production.
After the war, demand declined sharply and farmers began to look for other uses for the plant and its products. Edible rapeseed oil extracts were first put on the market in 1956–1957, but these suffered from several unacceptable characteristics. Rapeseed oil had a distinctive taste and a disagreeable greenish colour due to the presence of chlorophyll. It also contained a high concentration of erucic acid. Experiments on animals have pointed to the possibility that erucic acid, consumed in large quantities, may cause heart damage, though Indian researchers have published findings that call into question these conclusions and the implication that the consumption of mustard or rapeseed oil is dangerous.[11][12][13][14][15] Feed meal from the rapeseed plant was not particularly appealing to livestock, due to high levels of sharp-tasting compounds called glucosinolates.
Plant breeders in Canada, where rapeseed had been grown (mainly in Saskatchewan) since 1936, worked to improve the quality of the plant. In 1968 Dr. Baldur Stefansson of the University of Manitoba used selective breeding to develop a variety of rapeseed low in erucic acid. In 1974 another variety was produced low in both erucic acid and glucosinolates; it was named Canola, from Canadian oil, low acid.
A variety developed in 1998 is considered to be the most disease- and drought-resistant variety of Canola to date. This and other recent varieties have been produced by using genetic engineering.
An Oregon State University researcher has determined that growing winter canola for hybrid seed appears possible in central Oregon, USA. Canola is the highest-producing oil-seed crop, but the state prohibits it from being grown in Deschutes, Jefferson and Crook counties because it may attract bees away from specialty seed crops such as carrots, which require bees for pollination.
Canola was originally a trademark but is now a generic term for this variety of oil. In Canada, an official definition of canola is codified in Canadian law.[16]
Africa: In the South of the Republic of South Africa,Canola was planted for the first time in 1993 in the region called the Overberg near the town called Swellendam. Swellendam's farmer's Co-operative, SSK- Sentraal-Suid Koöperasie started a oil refinery called Southern Oil Limited(Soill),according to the Afrikaans newespaper Die Burger's article on the 24/07/2009 it is the only Canola refinery in South Africa and refines about 3 500 tonnes per month.
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Canola oil is low in saturated fat, is high in monounsaturated fat, and has a beneficial omega-3 fatty acid profile. The Canola Council of Canada states that it is completely safe and is the "healthiest" of all commonly used cooking oils.[20] It has well established heart health benefits[21] and is recognized by many health professional organizations including the American Dietetic Association, and American Heart Association, among others.[22][23][24][25] Canola oil has been authorized a qualified health claim from the U.S. Food and Drug Administration[26] based on its ability to reduce the risk of coronary heart disease due to its unsaturated fat content.
In 1999 an e-mail was widely circulated that falsely claimed that canola oil was harmful to human health . This is now considered an email hoax making unsubstantiated claims. Reputable research studies confirm that canola oil is a safe and healthy choice.[27][28][29]
Genetically engineered canola which is tolerant to herbicide was first introduced to Canada in 1995. Today 80% of the acres sown are genetically modified canola.[30] A 2010 study found transgenes in 80% of wild or "feral" varieties in North Dakota, meaning 80% of those were of "genetically modified" or genetically engineered varieties. The researchers stated that "we found the highest densities of [such transgene-containing] plants near agricultural fields and along major freeways, but we were also finding plants in the middle of nowhere" adding that "over time,..the build-up of different types of herbicide resistance in feral [natural] canola and closely related weeds,..could make it more difficult to manage these plants using herbicides."[31]
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 his field was contaminated with Monsanto's patented Roundup Ready glyphosate-tolerant canola. The supreme court ruled that Percy was in violation of Monsanto's patent because he had intentionally grown the crops land, but he was not required to pay Monsanto damages since he did not benefit financially from its presence.[32] On March 19, 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 $660 Canadian.[33]
The introduction of the genetically modified crop to Australia is generating considerable controversy.[34] Canola is Australia's third biggest crop, and is often used by wheat farmers as a break crop to improve soil quality. As of 2008 the only genetically modified crops in Australia were non-food crops: carnations and cotton. In 2003, Australia's gene technology regulator approved the release of canola altered to make it resistant to the herbicide Glufosinate ammonium.[35]
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