Every year in the spring, yellow fields light up a large part of the Czech Republic.
Rapeseed is blooming, a plant that is the subject of many discussions and myths.
Whether you are one of its supporters or opponents, it is certain that humanity needs this oil.
It is used not only in the food industry, but also in cosmetics and, of course, as biofuel.
Do you also think that rapeseed oil is of poor quality and should not be used in cold cooking?
And is rapeseed really just chemistry, as is often claimed?
Follow the footsteps of this controversial plant with us.
What is canola?
Rapeseed or, more precisely, oilseed rape is one of the most famous oilseeds in the world. We all know its tiny yellow flowers, which then form a pod that hides the seeds. Oil is obtained from them, which has a variety of uses not only in the kitchen. Currently, however, rapeseed is grown mainly for the production of biodiesel. Rapeseed rutabaga exists in two subspecies:
- Brassica napobrassica – is grown mainly for its tubers, which serve as food and fodder
- brassica napus – is grown primarily for the production of oil and biofuels
Canola as we know it was bred in the 1960s and 1970s in Canada when scientists succeeded in obtaining a plant that, unlike the original canola, did not contain toxic compounds known as erucic acid and glucosinolates.
Currently, rapeseed oil has three main areas of use:
- rapeseed oil – each pod contains small black seeds, oil makes up almost 45% of rapeseeds. Its light texture, flavor and high smoke point make it a versatile choice for kitchen use.
- rapeseed meal – is an important feed for a number of farm animals, its advantage is its high protein content. It is actually the solid parts of the seed after the oil has been extracted.
- biofuels – rapeseed oil is the most commonly used vegetable oil for the production of biodiesel.
Is canola genetically modified?
Since the canola plant was “created”, many varieties have been bred. But most canola, especially that originating in North America, is genetically modified (GMO) to improve the quality of the oil and increase the plants’ resistance to herbicides. In the European Union, and thus also in the Czech Republic, the cultivation of genetically modified rapeseed is not allowed.
By the way, regardless of whether rapeseed oil comes from genetically modified or non-genetically modified plants, it is exactly the same. Only one gene was modified in herbicide-tolerant canola. This gene is a protein, but all proteins are removed from rapeseed oil during processing. This means that the oil produced from the genetically modified seed is ordinary rapeseed oil, with the same composition as the oil obtained from non-genetically modified plants.
Allergy to canola
Rapeseed is often considered one of the plants to which many people are allergic to pollen. But it is not quite true. First of all, due to its greater weight, rapeseed pollen is not able to travel as far as the pollen of grasses or some trees, which means that you will only feel an allergy to rapeseed in close proximity to a flowering field. Secondly, most people suffer from what is known as cross-pollen allergy, that is, they are allergic to a combination of different pollens. And at the same time as the canola blooms, a number of grasses, trees and cereals also bloom.
Rapeseed as a new protein source
Rape meal, which is actually a waste after obtaining oil, is used today as feed for many farm animals, cattle, pigs and poultry. However, for several years there have also been projects promoting canola as a possible future vegetable protein for human consumption. Already in December 2020, for example, the Canadian company Merit Functional Food started producing a number of products based on rapeseed protein. The following video shows what such rapeseed consumption could look like.
Rapeseed oil is processed similarly to other seed oils. After thorough cleaning, the rapeseeds are crushed to extract the oil. The seeds can be cold pressed, but are usually heated and shelled to release more oil. After extraction, the oil can be further refined to obtain a clear oil with a neutral taste. Rapeseed oil processed in this way can be stored at room temperature for approximately one year.
How is refined rapeseed oil made?
The production process of highly refined rapeseed oil takes place in many stages.
- Cleaning – the seeds are separated and cleaned to remove impurities.
- Treatment and dehulling – the seeds are preheated to a temperature of approximately 95°C and then dehulled using roller mills to form flakes.
- Cooking – the flakes are then cooked in a series of steam cookers. This heating process usually takes 15-20 minutes at a temperature of 80°-105°C.
- Pressing – cooked rapeseed flakes are pressed using screw presses, this procedure removes 50-60% of the oil from the flakes, the rest is extracted in another way.
- Solvent extraction – the remaining oil is extracted from the remaining flakes using a chemical called hexane.
- Desolventization – hexane is removed from rapeseed meal by heating it to 95-115 °C and using steam.
- Oil processing – the extracted oil is refined by various methods, such as steam distillation, phosphoric acid treatment and filtration through acid-activated clays.
In addition, canola oil produced for margarines undergoes hydrogenation, a process in which hydrogen molecules are introduced into the oil to change its chemical structure.
Rapeseed oil and other oils
One of the benefits of canola oil is its high smoke point. Knowing the smoke point of an oil is very important, because once it is exceeded, toxic fumes and harmful free radicals begin to form. The smoke point of rapeseed oil, depending on the type of refining, is approximately 230°C, which is higher than common sunflower, olive, coconut or vegetable oil. For this reason, it is suitable for frying or frying.
|Oil type||Smoke point|
|Rapeseed oil||230 °C|
|Olive oil||210 °C|
|Vegetable oil||220 °C|
Despite many myths, rapeseed oil is one of the healthiest oils, for example it has the lowest saturated fat content of all common cooking oils. The polyunsaturated fats in canola oil include 21% linoleic acid, an omega-6 fatty acid, and 11% alpha-linolenic acid, a type of omega-3 fatty acid.
Comparison of canola oil with other oils that we use most often in the kitchen, as well as with butter and lard.
|Energy||884 calories||884 calories||884 calories||892 calories||717 calories||902 calories|
|63.3 g||19.5 g||73 g||6.33 g||23.4 g||45.1 g|
|28.1 g||65.7 g||10.5 g||1.7 g||3.01 g||11.2 g|
|7.36 g||10.3 g||13.8 g||82.5 g||50.5 g||39.2 g|
How to use rapeseed oil in cooking?
Rapeseed oil is widely used in the preparation of a wide range of dishes, not only Czech, but also Chinese, Indian or French cuisine. It can be fried, stewed, cooked, sautéed, baked, and thanks to its neutral taste, unlike some other oils, you won’t recognize it in food.
- You can fry different types of steaks, pork, chicken, veal and vegetable in rapeseed oil. Do you know how to prepare tender fried steaks? Let the canola oil heat up before putting in the food, otherwise the food will soak it up too much and the result will be greasiness and little crunch. It will serve you just as well if you have a weakness for fried cheese or breaded mushrooms.
- You can also use rapeseed oil as a base for a variety of one-pot dishes , such as meat and vegetable stews. You can just as well prepare Spanish birds, Moravian sparrows, goulash or Chinese dishes on it.
- If you like grilling meat or vegetables, you can use rapeseed oil in marinade recipes .
- Despite some myths, rapeseed oil is also suitable for cold cooking, it can be used, for example, in the preparation of various toppings for vegetable salads and also for various homemade dressings.
- You can also use a small amount of rapeseed oil to make homemade mayonnaise . You can then use mayonnaise not only for salads, but also as a base for various toppings for hot and cold dishes.
- Last but not least, oil can also be used in baking, when you use it to replace butter or other types of fat in the dough. The resulting dessert will be supple and soft. Try using it, for example, when preparing a puff pastry.
Rapeseed oil and health
Rapeseed oil is widely considered a healthy oil because it is high in monounsaturated fats. A significant amount of scientific research suggests that canola oil can have a positive effect on several chronic health problems, including heart disease, diabetes and metabolic syndrome. The results confirm, for example, that:
- bad blood cholesterol dropped by an average of 16.2% when volunteers consumed canola oil instead of a diet high in saturated fat for 12 weeks.
- a low glycemic load diet with canola oil helped improve both cholesterol and blood glucose control in patients with type 2 diabetes.
- in people at risk of metabolic syndrome who consumed canola oil, the amount of abdominal fat and blood pressure decreased.
Potential risks of canola oil
One of the alleged main disadvantages of canola oil, which many people fear, is that it does not come from a “natural plant”, but from genetically modified plants, also known as GMOs. There is some controversy over whether GMOs themselves are safe in the long term.
Long-term safety studies are not yet available. For this reason too, there are extensive discussions about whether GMOs are healthy or unhealthy. While genetically modified canola is not allowed in the EU, it is in America, which is why it is so important to pay attention to where the oil comes from.
What is made from canola?
Like many other crops, rape also has other uses in addition to food use. For example, it is one of the raw materials for the production of biofuels, it is mainly used for the production of low-carbon biodiesel. Rapeseed biodiesel is much more environmentally friendly than oil-based diesel, reducing greenhouse gas emissions by up to 90%. Specifically, biodiesel reduces emissions of carbon monoxide, solid particles and sulfates. Biodiesel also enables better engine performance and lubrication.
In addition, rapeseed oil is used in the chemical industry to produce plastics, resins, paints, varnishes, lubricants, soap and other cosmetics, as well as articles made using plasticizers, such as tires.
Biodiesel is produced from rapeseed oil through a refining process called transesterification. The oil is mixed with alcohol to remove the glycerin, which can be used in skin creams, soaps and other beauty care products. The rest of the crushed seeds will be used in the form of rapeseed meal. Biodiesel in its pure form is known as B100, but more often it is mixed with regular diesel, resulting in B5 (5% biodiesel and 95% diesel) or B20 (20% biodiesel and 80% diesel).
Oilseed rape belongs to the family of cruciferous plants, just like cauliflower, cabbage, cabbage, broccoli or mustard. It probably originated in the Mediterranean by crossing cabbage rutabaga and rape rutabaga. The first evidence of the production of rapeseed oil dates back to the Middle Ages, but its cultivation did not spread in Bohemia until the end of the 19th century. Rapeseed bred in the 1960s and 1970s by Canadian scientists was named canola, which is a combination of the English words Canada and oil. Canada is currently the largest producer of canola, followed by China and India. In Europe, it is grown the most in Germany and France, in the Czech Republic it actually covers approximately 15% of arable land.
In the world today, rapeseed oil is grown in two main varieties. The spring form of canola is grown in areas with severe winters or in warm areas where winter as a season is almost absent. In the Czech Republic and Europe, mainly winter rape is grown, which is in the fields almost all year round. It is mainly sown in August and harvested in July of the following year.
Winter rapeseed is a relatively demanding crop to grow. It requires deeper and well-prepared soil, fertilization and, above all, intensive protection against pests, diseases and weeds. Growing canola needs the most fertilizers in the spring months, various nitrogen fertilizers are used in combination with organic fertilizers. As for herbicides, their application is necessary already in autumn. In particular, broad-spectrum herbicides are used to kill “weedy” plants that could represent competition for rapeseed in the future. These plants are, for example, the shepherd’s hen’s capsule, the peasant’s sedge, the hornwort or the cocoyam.
The harvest of winter canola can be very negatively affected by the weather, especially by intense summer storms with hail and torrential rain. These vagaries of the weather cause damage to the rapeseed, especially the laying of the plants, which makes it difficult for the subsequent movement of the harvesters, and possibly also the opening of the pods hiding the seeds.
Does canola harm the soil?
Although, on the one hand, rapeseed is an important honey-bearing plant, thanks to its deep roots it fulfills an anti-erosion function in terms of soil and at the same time retains water well in the soil, its cultivation is also associated with the use of a considerable amount of chemicals, especially fertilizers and pesticides, as it is susceptible to pests . These sprays can have a negative effect on the health of bee colonies.
Grazing young green canola is not good for forest animals either, causing digestive problems. The long-term intensive cultivation of rapeseed also depletes the soil, for this reason it is necessary to regularly alternate it with other crops in the fields. It can be grown on the same field after three years at the earliest.