By Cindy Green

St. Paul, Minn. — Like most of us, Bob Herzfeld never dreamt that someday he’d be suggesting ways to control the problem of ... hog odor.

But it’s just possible that the Cenex/Land O’Lakes marketing manager and his colleague, Joe Gednalske, may yet see their names go down in history, right next to hog manure. Because following their senses led to the invention of a soy-based additive that can keep odors under wraps.

Now in the final testing stages, Cenex/Land O’Lakes’ newest product, “CLOR 1,” is a spin-off of a previous Herzfeld/Gednalske invention called Preference, an herbicide adjuvant that AURI helped formulate and bring to market eight years ago. Preference, which improves the performance of herbicides it’s blended with, has been “hugely successful,” Herzfeld says.

Sniffing out a clue

Three years ago, Herzfeld noticed there wasn’t any 2,4-D smell coming from the herbicide-Preference blend he sprayed on his backyard brush. He experimented with different batches, spraying herbicides with and without the adjuvant, and observed that Preference consistently eliminated herbicide odor.

Around the same time, Cenex/Land O’Lakes agronomist Joe Gednalske began to notice the same odor-stifling effect in farm field trials. After more testing, Herzfeld and Gednalske applied for and received a patent on Preference as an herbicide odor-reducer in April 1997.

Preference for pigs?

During internal marketing meetings, Herzfeld suggested that farmers wanting to control spray odors — especially on fields near communities — should use Preference. Some employees working around hog installations joked, “Well, gee, it sure would be nice if this could work on hog manure.” Herzfeld didn’t laugh; he decided to take the challenge and had Preference tested at a swine research facility in Iowa. “In 25 out of 26 manure samples tested, it made a definite improvement,” he says.

Preliminary tests in 1995 at University of Wisconsin dairy barns in River Falls were also positive. Preference treatments not only reduced odors but required less water to flush barns.

“Every year that researchers spread the lagoon (contents) in fields, one or two would call and complain. This year they had no calls. They spread it and nobody knew it was out there.” Once again, Herzfeld and Gednalske applied for a patent on the reformulated Preference, dubbed CLOR 1, which they received in June. It was their seventh adjuvant-related patent.

Sole soy solution

Although a gamut of new products are being tested on hog odor, this is the only one that’s soy-based, Herzfeld says. “Some people have done work on soy oil for dust control, and controlling dust by misting could control odor.” Since soy oil is expensive, this control method is prohibitive, Herzfeld says. By contrast, CLOR 1 utilizes soapstock, a cheaper byproduct of soy oil refining, rather than pure oil.

As he did eight years ago with Preference, Herzfeld went to AURI for help testing his new product. His company, the Cenex/Land O’Lakes Agronomy Company, is a smaller joint-venture subsidiary of the two larger co-ops. “We don’t have an R&D facility ... our main mission is to distribute fertilizer and crop protection products to local co-ops.”

Jack Johnson, AURI waste utilization specialist, says it made sense for AURI to get involved because “this is a value-added product, derived from soybeans, that happens to control hog odor,” adding that “this is a Minnesota company, a co-op.” The soapstock used is also produced in rural Minnesota, at the Honeymead plant in Mankato.

Proving it in the pits

Testing started last summer at a four-barn location near Waseca and will continue through this year, Johnson says. CLOR 1 is poured over manure pits, “creating a layer on top so when reactive gasses come up through the manure, it keeps them from coming off — like a sealant. So far, it’s been active on hydrogen sulfide (one of the major culprits of odor monitored by state government regulators),” Johnson says.

The University of Minnesota is assisting with Johnson’s weekly tests, and the Minnesota Soybean Growers Association and AURI are providing funding. The co-op is covering the bulk of test costs in Minnesota and at Iowa State University, however. And if the product is commercialized, Cenex/Land O’Lakes will pay AURI back with interest.

“We’re looking at further substantiation, that it works well enough to make claims,” Johnson says. “We’re establishing what odor components it affects the most. We’re helping Cenex/Land O’Lakes establish dosage rates, how often it should be applied, and we’re looking at the economics to determine if it’s cost effective.”

Researchers will look at results under different variables, such as temperature, feed rations, barn size and application method. Both Herzfeld and Johnson recognize it could be a year or two before the product is ready to roll out into the marketplace.

Herzfeld says they’ll look at potential benefits beyond odor control. “Will there be a healthier hog that can go to market faster? And if we can control ammonia, we might keep more nitrogen in the manure, creating better fertilizer value. Then it becomes a more economical decision” to use the product.

If it works, “it’s a tremendous market. “We’re having trouble figuring out just how big this market is,” Herzfeld says. CLOR 1 could be used for odor control in dairies, sugar beet lagoons — “We’ve even tried it on a mink farm with some success.”

Herzfeld expects CLOR I to be popular with hog farmers wanting to support the soybean industry — just as farmers have purchased Preference. “It’s a farm product for a farm solution.”