What Is Rapeseed?
Rapeseed (Brassicaceae) is a member of the mustard family and one of the most widely grown legumes worldwide. It is cultivated primarily for its edible seeds which are used as animal feed or in the production of oils and waxes. The plant is native to Europe, Asia Minor and North Africa.
The term “rapeseed” was first coined by botanist William Henry Perkin in 1834. It refers to the seeds of the species Brassica rapa L., commonly known as rapeseed. These seeds have been traditionally used for food, fuel and industrial purposes since ancient times. They were also extensively cultivated in Europe during the Middle Ages when they were valued for their medicinal properties.
In the early 1900’s, the cultivation of rapeseed was restricted in Canada due to environmental concerns. However, it was reintroduced in the 1970’s and today it is one of the most popular crops throughout much of North America. It is also a major crop in many other countries including India, China and South Africa.
It is estimated that there are over 100 million acres under cultivation worldwide with annual yields exceeding 150 million bushels per acre. The leading producers are China, India, Canada, the United States and Argentina.
Rapeseed oil is edible vegetable oil obtained from the seeds of the rapeseed plant. It has been used as a fuel for centuries and was a major source of energy during World War II. More recently it has become widely used in the biofuel industry.
It is also used as a lubricant, in cosmetics, soaps, candles and paints and to give foods a nutty flavor. The oil is also used in the production of artificial latexes,styrene butadiene rubber, resins, lubricants, dyes, waxes, crayons and much more. It is used to fortify food products and it is also used as a feed supplement for cattle.
Rapeseed has been cultivated since ancient times. It was commonly used by the ancient Romans and during the Middle Ages when it was extensively cultivated throughout Europe. In North America, it was introduced in the seventeenth century and for a time, it became a primary cash crop in the colonies.
It is known by a variety of different names including oléum, jatropha, Chinese oilseed, Japanese oilseed, Indian sunflower and gomella. The name jatropha can cause confusion as it is more commonly applied to an entirely different plant known as the jatropha of the spurge family.
The term “rapeseed” refers to the seeds of the plant and not the plants themselves. There are two types of rapeseed plants in the genus Brassica. These are the B. napus (known as the oléagineux type) and the B. campestris (known as the campestris type).
The oléagineux type is cultivated for its seed oil and the campestris type is cultivated for its oil and meal.
For a time, rapeseed was one of the main crops grown in Canada, in fact, it was once known as the Canadian Oil-Tree. It was later replaced by the more popular wheat and corn but there has been a resurgence of interest in rapeseed over the past few decades.
The largest producers of rapeseed today are China, India, Canada, the United States and Argentina. Rapeseed is very easy to cultivate requiring little more than plenty of sun and infertile soil. It can be grown in a variety of climates but thrives in dryer regions. There are four main types of rapeseed, these being the following:
*Brassicas: these have a high meal yield. They also contain high levels of glucosinolates.
*Gigas: these are generally of good quality (high in oil and low in glucosinolates) but have a low yield of meal.
*Oleiferas: these are high in oil (20-35%) and meal but also have high glucosinolate levels.
*Faba: these are low in oil and glucosinolates but have a high meal yield.
In Canada, the plant is grown in central and western parts of the country but there has been a move toward growing it in the east as well. There are two main types of rapeseed grown in Canada, these being the following:
1) BR95-INRA (also known as WCD2)
This variety has been cultivated since 1995. It was developed by researchers in France and is very common in Europe and North America. It is high in glucosinolates and has a meal yield of 20-25%.
This variety was developed in Canada. It is low in glucosinolates (which means it has a lower goiterogenic activity) and has a high meal yield of 35%. It also has an excellent yield potential and is resistant to disease. It is ideal for harsh climates.
The United States also grows a number of other varieties including the P22, P23 and VR54.
Farmers typically grow rapeseed (except for in Canada) from September to October but it can be grown between May and July. The longer it is grown, the higher the glucosinolate content of the seed. Farmers harvest the crop when the plants begin to turn yellow. At this point, they pull up the plants, put them in a field and allow the oil-rich seeds to drop off. The leftover stems and leaves are usually burned.
The leftover seeds are then taken to oil mills where they are processed and made ready for market.
This short article about biology is made by Zebulum Kamba.
In this website you can find more information about rapeseed oil.
Sources & references used in this article:
From rapeseed to canola: A brief history of research for superior meal and edible oil by JM Bell – Poultry Science, 1982 – Elsevier
Canola and rapeseed: production, processing, food quality, and nutrition by U Thiyam-Holländer, NAM Eskin, B Matthäus – 2012 – books.google.com
Rapeseed meal-glucosinolates and their antinutritional effects. Part 1. Rapeseed production and chemistry of glucosinolates. by R Mawson, RK Heaney, M Piskuła, H Kozłowska – Die Nahrung, 1993 – europepmc.org
Preclinical evaluation of rapeseed, raspberry, and pine bark phenolics for health related effects by S Vuorela, K Kreander, M Karonen… – Journal of agricultural …, 2005 – ACS Publications
Epidemiology of Sclerotinia stem rot of rapeseed in Saskatchewan by RAA Morrall, J Dueck – Canadian Journal of Plant Pathology, 1982 – Taylor & Francis
11 The Evaluation of the Economic and External Health Benefits from Canola Research by R Gray, S Malla – Agricultural Science Policy, 2001 – books.google.com