"We know that the one percent linolenic acid oil performs very well. The tests by the food industry will determine if elevating the oleic acid has made the oil even better," said Professor Walter Fehr, lead researcher in the project.
The research is part of Iowa State's ongoing search for soybean oils that do not require hydogenation, a process that can prolong shelf-life but also leads to trans fatty acids.
Numerous studies in the literature show that trans fatty acids raise serum levels of LDL-cholesterol, reduce levels of HDL-cholesterol, can promote inflammation, can cause endothelial dysfunction, and influence other risk factors for cardiovascular diseases (CVD).
Soybean oil containing low levels of linolenic acid is already available commercially, most notably with Cargill's Vistive oil with a linolenic acid content of three percent, produced from Monsanto's Vistive soybean. The soybeans are reported to have enjoyed significant success on the back of an industry move to slash the trans fat content of foods.
According to market researcher ACNeilson, US sales of products already labeled 'no trans fat' increased 12 percent to $6.4bn for the 52 weeks ended October 2, 2004, compared with the previous 52-week period.
Iowa State have already produced a soybean oil with a linolenic acid content of only one percent.
"Our one percent linolenic acid oil does not require hydrogenation and has been adopted by the food industry in a range of products," Fehr explained.
"We wanted to find out if it would be possible to make the one percent linolenic acid oil even more useful by increasing its content of oleic acid, the same monounsaturated fatty acid found in olive oil. We were not sure whether we could combine the two traits in a variety because it had never been done before."
High levels of oleic acid and the accompanying low levels of linolenic acid are attractive, Professor Fehr said, because oleic acid is more stable than linolenic.
The researchers used soybeans from Saga University in Japan, developed using conventional breeding techniques, which had an oleic acid content of about 50 percent. Standard soybeans have an oleic acid content of about 28 per cent.
But the soybeans could not be cultivated in Iowa due to seasonal weather differences between the Midwest and Japan, and also because the linolenic acid content was too high to avoid hydrogenation.
Professor Fehr and his colleagues set about using conventional breeding techniques to transfer the genes responsible for the elevated oleic acid trait into the soybean varieties with the one percent linolenic acid content that could be grown in Iowa.
"The results were better than we had anticipated. The oleic acid of the soybeans was greater than 50 percent and the linolenic acid was only 1 percent," said Fehr.
The unique soybeans were developed with funding from U.S. soybean farmers through the Iowa Soybean Association and United Soybean Board.
And now the researchers are looking for food industry participation to test the oil and to examine if the novel soybean oil could be used in applications that are usually off-limits to non-hydrogentated soybean oil - namely cereal and energy bars and non-dairy creamers.
Professor Fehr told FoodNavigator-USA.com that commercial production of the oil would depend on its performance compared to a normal oleic acid/ one percent linolenic oil already in commercial production.
"It is a chicken and egg situation," said Fehr. "The oil will not be produced if there in no commercial interest in it."
Companies interested in participating in the tests should contact Professor Walter Fehr at Iowa State University.