Research into a new process for producing mint oil could lower farmers’ costs and breathe new life into the state’s mint industry.
But even if the process, which involves using a microwave, proves successful, several Central Oregon experts say, it will not return the region to its heyday, when Jefferson County growers led the state in peppermint production.
Farmers in the region face another challenge before they can get to production: a pathogen in the soil that prevents the plant from even growing lingers in the fields and, so far, resists efforts to manage it.
From 1976 to 1990, Jefferson County dominated the state’s production of peppermint grown for oil, outgrowing every other county and producing more than 500,000 pounds in 12 out of 15 years, according to Oregon State University Extension Service records. In 2008, those records show, no peppermint was grown for oil in Jefferson County, although some farmers grew mint for the leaves, which are used in tea.
In the peak years of peppermint production, agronomist Glenn Ridgway recalls, stills ran 20 hours a day for a month, forcing steam through the mint to release the oil used in toothpaste, candy and other products. This year, the acreage equaled about 45 hours of work for a still.
Competition from regional and international growers, combined with reduced demand and disease, knocked Jefferson County off the top of the peppermint pile.
Reducing the costs to produce the oil could help. The traditional process requires fuel, commonly diesel or natural gas, to fire boilers and produce the steam to extract the oil from the plant.
To run a boiler for a minute takes a half gallon of diesel, said Ridgway, who works for Wilbur-Ellis agribusiness in Madras. A gallon of diesel has been selling for about $2.85 recently.
But researchers are attempting to use a microwave in the distillation process. It could lower production costs and improve safety, as well, said David Hackleman, who previously held an endowed chair at Oregon State University’s School of Chemical, Biological and Environmental Engineering and served as former chief technologist for Hewlett-Packard.
Hackleman, who is currently compiling results from tests conducted in the summer, said the method works and saves energy.
“It looks good,” he said.
Various industries use microwaves, to dry textiles for example, according to the U.S. Energy Department. Hackleman said radiation exposure is not an issue.
More work is needed on the use of microwaves, he said, and an industrial partner would need to be found to start production. Optimistically, if everything fell into place, the process could be available in two to five years.
While microwaves may save money for some growers if developed, Powell Butte farmer Lynn Lundquist said it will not likely help much in Central Oregon, unless something can be done to rid the soil of a pathogen known as verticillium wilt, or simply wilt.
“That’s usually what really causes you to get out of the mint business,” said Lundquist, who also is a Crook County commissioner and former state lawmaker.
In past years, Lundquist may have had hundreds of acres on his 350-acre farm in peppermint. In the upcoming year, he plans to plant maybe 60, he said.
He’s tried to kill off the disease in his soil through fumigation. But within four years, it came back.
“I’m minted out, so to speak,” he said. “I’m pretty much on the way out.”
Scientists at OSU’s Central Oregon Agricultural Research Station in Madras have been seeking a solution to wilt, said Rich Affeldt, extension crop scientist.
They’ve stressed to growers the importance of sanitizing farm equipment and crop rotation. They’ve tried chemical controls, he said, and so far, two fungicides do not look very promising, and they’ve just started work with potential biological methods, such as looking for an organism that can be cultured and will stop wilt.
Affeldt is optimistic. Biological efforts have worked on other crops wasted by wilt.
“I think if this doesn’t work,” he said, “the only other route ...would be to look to some type of GMO (genetically modified) mint” that would be resistant to wilt.