Canola leads oilseeds as health benefits emerge GRDC invests in three year program by Maria Taylor
Think of a natural product which benefits developing brains and eyes; a product which has anti-inflammatory properties; is good for the heart and circulatory system; and may be useful in combating disorders such as diabetes. Hard to imagine? There's growing scientific evidence that the answer lies in Australian grain oils, led by Canola.
Health authorities have recommended for some time that unsaturated vegetable oils, which come into the diet mainly as margarines and cooking oils, can help maintain a lower blood cholesterol level.
The exciting news now is that scientific investigators are looking more closely at grain oils for a whole range of other health benefits — those outlined above.
They're finding the healthiest oils are ones with a certain fatty acid profile characterised by a relatively high alpha-linolenic (ALA) level. That's related to findings that increasing the amount of vegetable oil ALA in the human diet can produce positive health effects similar to the proven benefits of consuming fish oil.
Scientists and food retail manufacturers are turning to Canola because it is the Australian oilseed, grown in commercial quantities, which offers the best A L A profile and a low level of saturated fat as well. In addition, a specially bred sunflower oil offers a good example of oilseed potential.
That was the good news for grain growers and consumers coming out of a unique workshop recently held in Sydney. Hosted by the Grains Research and Development Corporation (GRDC) and Meadow Lea Foods Ltd, the meeting brought together many of Australia's foremost medical nutrition researchers to forge common ground for collaborative work and for talks with industry and grower representatives.
Reports at the meeting strengthened the claim for Australian oilseeds to become mainstream 'health foods'. The evidence in the scientific literature is now being expanded through combined GRDC/Meadow Lea investments, totalling almost $1 million, in a three-year research program. Ground Cover will report on some of these projects individually in upcoming issues.
Dietary research is being supported by growers at the University of Sydney, CSIRO Division of Human Nutrition, Flinders University, Royal Melbourne Institute of Technology, University of Melbourne, Baker Medical Research Institute, Royal Adelaide Hospital, Royal Alexandra Hospital for Children, University of Wollongong with St Vincent's Hospital and the University of Western Australia.
Getting the most ALA
Besides supplying energy, some fat compounds appear to be good for you. Fish oil in particular is known to be high in EPA and DHA (eicosapentaenoic acid and docosahexaenoic acid), two fatty acids which are important for regulating the behaviour of body cells. These fatty acids have been identified in research on blood clotting, inflammation, retinal functions, infant neutral pathways, coronary heart disease and metabolic disorders including diabetics.
But a lot of people don't eat fish or they equate fish oil with unpleasant childhood memories of cod liver oil. In any case, fish oil doesn't keep well under commercial conditions.
The important thing to remember about those 'healthful' fatty acids in fish oils, EPA and DHA, is that they are so-called omega-3 fatty acids. Enter grain oils, which are more palatable than fish oil. Vegetable alphalinolenic acid (ALA) is also an omega-3 fatty acid. In the body, A L A converts to EPA and DHA.
Here's the complicated bit. How much A LA is converted, from say 5 gms of margarine, is directly related to the amount of A L A in the oil compared with the level of another fatty acid: omega-6 linoleic acid (LA) — the ALA / LA ratio. Sometimes it's called the 'omega benefit'.
If there is a lot of LA, it dilutes the effect of ALA. Canola has the best ratio of ALA / LA in a food oilseed. (See comparison of oils and spreads table on bottom right.) Just how this ratio works to the body's benefit is the subject of a number of the research programs underway.
Another approach to good ALA
Sunola™ is another oilseed product under the combined GRDC/Meadow Lea research lens, but the A L A story is different. Sunola™ was specifically bred as a mono-unsaturated sunflower oil to be low in unsaturated fats. It also has little to no ALA or LA, to enhance its stability as a frying oil, for instance for the fast food industry. Oils high in ALA and LA lack stability when heated.
According to Chris Eyers of the Meadow Lea Food Advisory Centre, Sunola™ nevertheless has an 'omega benefit' as follows: the greatly increased levels of oleic acid (an omega-9 mono-unsaturated fatty acid) replaces much of the LA (omega-6) in the fatty acid chain. Therefore, ALA (omega-3) taken in from other sources can be more effective. (The relative values can be seen in the table below.)
Canola the golden grain
Meadow Lea Divisional Manager Research and Development Ron Bowrey is already convinced of the superior properties of Canola for the retail market (margarine, spreads and salad oil). And of Sunola™ which is a registered trade mark of Meadow Lea Foods Ltd, for the fast and commercial food industry, as well as for home use.
Dr Bowrey calls Canola the 'golden grain' because of its favourable ALA / LA ratio and overall healthy fat profile. "Nobody knew about that five years ago," he said. And the price is right for a manufacturer like Meadow Lea.
"Most importantly, Canola not only replaces imported oil but is less than half the price of other oils such as olive oil," he said.
Meadow Lea's Gold'n Canola product line, launched in 1990, is doing well with about 7 per cent of the retail margarine and cooking oil market. Dr Bowrey said the line has expanded to mayonnaise and cooking spray products with further products planned. (Other manufacturers have also started to promote the benefits of Canola).
Ted Wolfe, Professor of Agriculture at Charles Sturt University and GRDC Southern Region panel member, told the assembled scientists that Canola is now Australia's fourth largest grain crop (following wheat, barley and lupins) with almost 600,000 tonnes projected for this year's harvest and a fastgrowing export market.
The workshop promised that, in a year's time, a dozen or.so studies will have fleshed out details on the nutritional advantages of Australian oilseeds. Researchers will be closer to framing the best fatty acid profiles for retail, food services, infant food, and designer foods for specific medical conditions.
Subprogram 1.4.04 Contact: Mr Chris Eyers, Meadow Lei Foods Advisory Centre 02 700 6464