Quest to put health back into canola oil
GroundCover™ Issue: 117 | Author: Sarah Clarry
Marketers contend that many consumers would refuse to buy canola oil that was not bland, clear and odourless.
But PhD researcher Clare Flakelar from Charles Sturt University, Wagga Wagga, New South Wales, says the processing involved to achieve these aesthetics is at the expense of a healthier canola oil.
Ms Flakelar is conducting GRDC-funded research into the health benefits of three minor components of canola oil and how the refining process might be modified to preserve these compounds. Her findings have been accepted for publication in the international peer-reviewed Journal of Food Composition and Analysis.
Returns to canola growers are currently dictated by oil content, free fatty acids, moisture content, seed weights, impurities and seed defects.
To produce high-quality canola, breeders have targeted high oil content and high yields, blackleg resistance, drought and herbicide tolerance and, more recently, fatty-acid composition.
The newest research – including that being undertaken by Ms Flakelar – is looking to breed for compounds with enhanced nutritional benefits.
Canola oil is composed of fatty acids grouped together as triglycerol phospholipids and, to a smaller extent, free fatty acids.
Aside from these fatty acids, there is a larger group of minor components, some of which have important health benefits, including:
- tocopherols; and
Sterols are prominent in canola oil in its crude form. They aid in lowering low-density lipoprotein (LDL, or ‘bad’ cholesterol) and have cardiovascular benefits.
Tocopherols are vitamin E compounds. They are natural antioxidants and exhibit disease-fighting properties. Additionally, they are important for oil stability.
Carotenoids exhibit vitamin A activity. They are important for skin and eye health and in canola oil are found in the forms of lutein and beta-carotene. Lutein is the more prominent form of carotenoid in canola oil. It is not synthesised by the human body, so needs to be ingested.
Doctors often prescribe lutein supplements for patients who are exhibiting the onset of age-related macular degeneration.
“This is an exciting finding because lutein is receiving a lot of attention for its potential health benefits. My work has shown that Australian canola contains lutein at levels comparable to those reported from other countries,” Ms Flakelar says.
With a food source such as canola oil that is used for various food applications, a potential source of lutein in the diet would be an advantage worth pursuing.
Ms Flakelar’s research has three main streams.
The first stream is examining to what degree the canola variety influences the minor compounds and whether new varieties can be bred on the basis of these compounds.
“In a preliminary study in 2013 I looked at some of the more common varieties,” Ms Flakelar says.
“From these results we found variety has a significant influence on these [minor] compounds and that the range of these compounds in these varieties was significant and variable, from 9 milligrams per kilogram all the way up to 163mg/kg.”
The 2013 study will be used to support further research Ms Flakelar has underway to verify these assumptions.
The second stream of her research centres around the oil-refining process.
The commercial refining process heavily degrades the minor compounds – up to 40 per cent for sterols, 50 per cent for tocopherols and 90 per cent for carotenoids – due to the harsh techniques.
“Processors have stated that the primary reason for using such techniques is to provide consumers with the end product they prefer,” Ms Flakelar says.
“That is a product that is bland, odourless and close to clear in colour. But consumer preferences are shifting. We know where and at what stages of the refining process these compounds are lost,” she says. Ms Flakelar’s research is looking at how the refining process can be modified to retain them.
3. Consumer attitudes
The third research stream is looking at consumer preferences.
Early in her research, Ms Flakelar encountered a consumer who said she avoided vegetable oils because of a perceived health risk.
“Her comment sparked my interest in consumer attitudes towards vegetable oil,” Ms Flakelar says.
“Consumers are the ultimate dictator of profit so, as part of my research, I’ll be surveying consumer preferences and attitudes towards vegetable oils and whether there is scope for change within the industry.
“Consumers are moving towards more natural, minimally refined products,” she says. “Is there scope, therefore, to provide a more nutritious end product?”
Already there is international interest in her work. She is currently in Saskatoon, Canada, presenting her findings to the 14th International Rapeseed Congress.
Ms Flakelar says by verifying that the canola variety itself is important in the balance of these compounds, it gives breeders the ability to drive this opportunity.
Further, if Australia is one of the first countries to develop these varieties it may lead to a demand for Australian canola elsewhere in the world, she suggests.
“Ultimately, and most importantly, we hope these developments will lead to profitable value-adding for canola growers and the Australian canola industry,” she says.
More information:Clare Flakelar,
0400 608 957,
GRDC Project Code UHS10457, GRS100664
Region Overseas, South, North