CALS scientists show common condiment also can become biodiesel, pesticide and animal feed
If you think mustard is only for your hot dog, think again.
For more than 28 years, Matthew Morra, a College of Agricultural and Life Sciences biochemist at the University of Idaho, has conducted research in the production of biodiesel and other products with the use of mustard seeds. It started out as a fundamental chemistry project, and is now in the hands of commercial investors.
“The fact that it has gone from very fundamental chemistry to approaching commercial viability is quite satisfying. My other projects have resulted in peer-referred publications, but this project has resulted in end products with tremendous utility,” Morra said.
Morra crushes mustard seeds to remove the oil, which is converted into biodiesel. A campus biodiesel facility produces fuel for the Vandal trolley that operates during special events.
Morra said UI has been producing biodiesel since the late 1970s, and is a leader in the production of biodiesel from oils from numerous sources including mustard, canola, soybean, insect larvae and coffee grounds.
“All you need is oil and you can convert it into biodiesel, and any engine can run on it without any engine modifications,” Morra said.
Part of Morra’s research is focused on the mustard-meal left over after the oil is removed. The mustard-meal contains chemicals called glucosinolates that the plant produces to defend itself against animals. The chemical defenses are present in many plants, including cabbage, broccoli, mustard, horseradish and radishes.
Morra said plants that produce glucosinolates also produce an enzyme, myrosinase, which initiates the chemical defense. Crushing the seeds unites glucosinolates and the enzyme, then the addition of water sparks a reaction that creates isothiocyanates. This chemical gives condiment mustard its bite and deters pests.
Morra said researchers have worked long and hard to use these isothiocyanates as biopesticides. These are similar in chemistry to synthetic pesticides that are commonly used to control plant pests.
The mustard species used to make mild, yellow hotdog mustard can be used to create this biopesticide.
Oriental mustard, also called brown, produces a meal used to kill nematodes. Yellow mustard meal does not kill nematodes but enhances the hatching of their eggs. Artificially enticing the eggs to hatch can leave the nematodes without a host to feed on and they die.
Louise-Marie Dandurand, director of the UI pale cyst nematode project, is testing Morra’s product against nematodes, a serious invasive pest of potato, and has found it to be very effective. She is working on determining the amount of organic product necessary to work against the nematode. There are few commercially available products that are effective against the pest.
Beyond pest control, Morra is also testing mustard-meal as a tool to slow or stop sprouting in stored potatoes. Early tests show the meal may be a promising alternative to the current favorite sprout-inhibiting chemical that federal regulators are now reviewing.
Morra said the process using his product is very straightforward. Water is added to the mustard-meal, creating isothiocyanate gas that is blown into a potato storage shed, stopping the spuds from sprouting. He said this has shown to be very effective at very low concentrations.
In addition to the glucosinalates found in mustard-meal, it also contains 5-6 percent nitrogen and about 38 percent protein, which is beneficial for dairy cows. After extracting glucosinolates, the detoxified seed-meal is valued as animal feed.
“Matt has demonstrated lots of potential and is working towards great things,” said Mark McGuire, CALS associate dean of research and director of the Idaho Agricultural Experiment Station.
McGuire is planning to work with Morra to test the residual meal as cattle feed.
From a farming and environmental standpoint, Morra said this research makes a lot of sense. These mustard plants are fantastic rotational crops in the Northwest because they will grow with only 10-15 inches of rain per year. Few insects attack them, so there is little need for insecticides. When rotated with a wheat crop, wheat yields go up. In addition, the amount of plant-available nitrogen increases after a mustard crop, and mustard crops also prevent erosion.
Morra has received dozens of grants over the years from the U.S. Department of Energy, and Department of Agriculture. He is currently working with a grant from the MJ Murdock Charitable Trust located in Washington.
Morra is also working with two commercial investors — one of which he has been collaborating with since 2007 called Farm Fuel Inc. located in Watsonville, California. The other, One Four Group of Meridian, Idaho, is interested primarily in potato sprout inhibitors.
It takes two years for new products to make it through EPA registration. Morra estimates that submission to the EPA will take place within the next six months.
“The idea is to have no waste products from this. We take the seed, crush it and use the oil. We take the seed meal, extract out the glucosinolates, and use those. And then we have the residual meal that we use for animals,” Morra said. “You have to have these various revenue streams or you can’t make it economically viable.”
Story by Jean Parrella, College of Agricultural and Life Sciences