A New Weapon Against Bacterial Disease

Bacteria that are resistant to antibiotics are one of the biggest problems facing public health today. About 800,000 children worldwide die before their fifth birthday from diarrheal diseases that evade treatment. The concentration of those diseases is highest in parts of Africa and Asia.

To address the problem, CALS biochemist Srivatsan (“Vatsan”) Raman hopes to harness the power of phages—viruses that infect bacteria but leave humans unscathed. With help from a grant from the Bill and Melinda Gates Foundation, Raman’s team is designing phages to specifically target bacteria that are causing diseases in infants.

Raman describes antibiotics—how doctors usually fight infections—as hammers that take out many bacteria, both harmful and beneficial. This means they can affect the entire human microbiome, which is the community of microbes on, inside and around the human body.

“We do not yet have the tools to selectively edit the composition of a microbiome,” Raman explains. But that is one of the goals of his lab’s work with phages. Unlike antibiotics, phages are very specific. A phage only infects one type of bacterial host. It is this specificity that presents Raman and his researchers with opportunities—but also some challenges.

Phages, which resemble lunar landers, locate bacterial hosts by attaching to specific receptors on the cell’s surface. Once they have found their host, some phages, called obligate lytic phages, quickly infect the cell and replicate. Once replication is complete, the new phage progeny burst out of the cell, ready to infect and kill the next available host.

Raman’s goal is to be able to control many steps in this process. He is investigating a way to engineer a phage that can be programmed to target specific bacteria. By changing just the “legs” of the lunar lander, the designer phage can target and eliminate any bacteria the researchers wish.

However, while destruction of bacteria is the ultimate goal, the process also creates problems. Many bacteria contain toxins that are released if the bacteria die in large numbers. So Raman’s team is also trying to control the rate at which phages infect and kill cells inside the body. “We can keep the phage on a leash and determine when and where it can infect,” describes Kelly Schwartz, a postdoctoral fellow in Raman’s laboratory.

Raman believes “designer phages” have great promise for human health.

“I was drawn to this research because designer phages can provide a potential solution to the antibiotic resistance problem,” notes Raman. “These bacteria are resistant to anything you throw at them and are killers in developing countries.

“And the next question, if we are successful, is ‘How can we turn these phages into actual medications that can be delivered to these areas?’ That challenge awaits us further down the road,” Raman says.

Vatsan Raman in his lab: The biochemist is engineering viruses that can vanquish harmful bacteria. Photo by Robin Davies/UW–Madison MediaLab at Biochemistry

The Inner World of Athletes

So many things typically distinguish accomplished athletes from the rest of us—greater strength and endurance, better balance, faster reactions—but one of the more surprising differences is that, according to dental studies, they also tend to get more cavities.

This intriguing phenomenon was the subject of a capstone course in microbiology this past spring, offering undergrads a chance to be part of a burgeoning worldwide scientific effort while using cutting-edge technology.

There are trillions of microbes in the human body; the community of microbes that lives in each of us is our microbiome. As more and more research focuses on microbiomes, it’s becoming clear they play a significant role in human health and wellness. Microbiology 551 students worked to add to that body of research using a next-generation DNA sequencer manufactured by the California-based company Illumina.

“It’s only our department and maybe one or two in California that are doing hands-on work with undergraduates in teaching this technique,” says co-instructor Melissa Christopherson. Christopherson teaches the course with Tim Paustian, both faculty associates in the Department of Bacteriology. “Having students conduct meaningful research with these modern techniques makes them more competitive in the job market and better able to navigate the field of microbiology.”

Students were tasked with comparing the oral microbiomes of athletes and nonathletes, using saliva samples. They sampled a range of students, from UW athletes to occasional exercisers to students who hadn’t exercised for at least five weeks. Once students collected and prepared the samples—including their own oral microbiomes—they sequenced the DNA and determined which microbes were present in each sample.

With so many samples, the students were able to look beyond the question of exercise to test other hypotheses they developed themselves.

“We wound up taking the same data set and asking other questions,” explains Samantha Gieger, who graduated in May with a BS in microbiology and genetics. “In groups of four or five, we looked at the effects of dairy, caffeine or using an electric toothbrush.”

Students presented their projects at a poster session last semester, and their work is currently being analyzed for publication. Their findings will become part of the growing research into microbiomes. Student Sophie Carr BS’16 and Christopherson were invited to the White House last spring for a summit announcing the launch of the National Microbiome Initiative.

As a capstone class, the course offered a research experience requiring students to integrate diverse bodies of knowledge to solve a problem. And it quickly proved invaluable as students considered next steps in their careers.

“I’ve learned so much—how to go about research, what to do when encountering a problem. Troubleshooting is such an important technique,” says Isaiah Rozich BS’16, then a senior majoring in microbiology and Spanish. “Figuring out which solution is best takes a lot of time, and it opened my eyes to what life as a researcher will be like. While it’s overwhelming, I think the end result is gratifying.”

PHOTO: On the case: Students compared the oral microbiomes of athletes to figure out why athletes get more cavities.
Photo by Sevie Kenyon

The Greenhouse as a Public Classroom

Just as some seeds yield tomatoes, carrots and lettuce, others grow community and partnership.

In a greenhouse in the northern Wisconsin town of Park Falls, all of those seeds are taking root with the help of CALS horticulture graduate student Michael Geiger, horticulture professor Sara Patterson and a team of dedicated local leaders.

“The greenhouse has opened doors to making healthier food choices, to education about gardening in local schools—and it’s given the university a presence in Park Falls,” says Geiger, who grew up in Arbor Vitae, some 50 miles away.

Geiger’s involvement with the Flambeau River Community Growing Center started four years ago when a friend in the area approached him for advice. Her group was seeking funding for a greenhouse project, and Geiger teamed with Patterson to identify possible revenue sources. They developed a proposal for the Ira and Ineva Reilly Baldwin Wisconsin Idea Endowment at UW–Madison.

By fall 2013, construction had begun on a 25-by- 50-foot vail-style greenhouse, built by community volunteers on a vacant lot donated by Flambeau River Papers just north of the mill. Plans call for the facility to eventually be heated with waste steam from the mill.

The Flambeau River Community Growing Center has gained popularity with community members and school groups interested in learning about plants and gardening. “It’s a greenhouse, but it’s also a classroom,” says Geiger.

Learners include children from the Chequamegon School District, who start seeds in the greenhouse and nurture seedlings until they can be transplanted to their own school gardens. Area 4–H groups grow plants and tend them in raised beds just outside the greenhouse. Master Gardener classes are held at the facility, and community workshops have included such topics as square-foot and container gardening as well as hydroponics. Kids have been delighted with sessions on soil testing and painting their own flowerpots.

“It’s clearly a benefit to build a connection between UW–Madison and the community, for the community itself—people from ages 3 to 90—and for the local schools,” Patterson says.

Community leaders and institutions have joined to fuel the center’s success. Its chief executive officer, Tony Thier, recently retired from Flambeau River Papers; UW–Extension has provided valuable educational and technical support; and volunteer opportunities draw professionals from various companies in the area. Park Falls attorney Janet Marvin helped the center gain nonprofit status last fall.

Thier says the center provides needed education for area residents. “It’s been very beneficial,” he says. “When I got involved, it really became a passion. I wanted to learn more about gardening and increase my skill. We try to involve the whole community.”

Geiger says the project has helped him in his academic career as he learned about project planning, gave presentations about the center at two national academic conferences and writes scholarly articles about his work there.

“I’ve been able to see this process through from an idea to reality,” says Geiger. “It’s been really rewarding.”

PHOTO – Michael Geiger (right) in the greenhouse at a hydroponic salad table workshop. The greenhouse features in-floor radiant heating and custom growing tables made of locally purchased white cedar and built by volunteers.

Photo credit – Michael Geiger

New Frontiers for No-Till

New Frontiers for No-TillWhen Jason Cavadini, assistant superintendent of the CALS-based Marshfield Agricultural Research Station, first started working at the station in spring 2013, he was told that no-till wouldn’t work in the area, with its heavy, poorly drained soils. But he still wanted to give it a try.

“Here in central Wisconsin, a big concern is, what do we do with the water? How do we get it to drain better? If no-till allows the soil to do that naturally, in our opinion it’s the best way,” says Cavadini. His interest in the method stems from experience on his family’s farm near La Crosse, where they have successfully used no-till planting for nearly 20 years.

Conventional tillage often involves turning and pulverizing the soil before planting with multiple passes of a tractor to chisel-plow, disk and smooth out the field. There are many advantages to this approach, including setting back weeds, helping the soil to dry and ensuring good seed-to-soil contact. However, it’s also fraught with issues such as soil compaction and erosion.

No-till, on the other hand, involves the use of a planter that seeds directly into the soil without the complete disruption and inversion of the surface. This alternative option, which has been shown to work well in other areas with other soil types, has reduced environmental impacts and helps build long-term soil structure. There’s also an economic benefit. “Fewer trips across the field with equipment means less fuel used,” notes Cavadini. “We have cut fuel usage and labor associated with spring planting by more than 50 percent since implementing no-till.”

Making the switch to no-till, however, involves some trial and error. Cavadini thought, “What better place to give it a try than the Marshfield station?”

“We started a group we’re calling Central Wisconsin No-Tillers,” Cavadini says. “We set a planter here on the station with different combinations of no-till tools. After we finished planting in the spring of 2014, we invited people to the station and told them what we found with our research planter. About 10 farmers showed up, but it was a very productive meeting, and we tried to address things that they were questioning.”

When Cavadini held a meeting for the group the following year, 46 farmers appeared.

So far, the no-till approach is working well at Marshfield, and the research station has expanded its use to include more crops. Corn was the starting point—“We experienced some of our highest corn yields ever on the station this year in no-till fields,” notes Cavadini—and now about 80 percent of the station’s plantings are done with no-till, including soybeans, wheat and alfalfa.

“A long-term, no-till soil that is firm at the surface but takes in water readily is what we are really trying to achieve here,” Cavadini says. “If we are successful, that will solve a lot of the challenges that central Wisconsin farmers face here every year.”

PHOTO—Jason Cavadini has had success with no-till on crops at the Marshfield Agricultural Research Station.

Photo by Sevie Kenyon BS’80 MS’06

Moth Mating, Disrupted

It’s no fun being a male moth in one of Shawn Steffan’s cranberry research plots. When the time comes to mate, it’s tough to find a partner.

Here’s why: Using an approach known as pheromone-based mating disruption, Steffan and his team dot their test fields with hundreds of dollops of pheromone-infused wax—known as SPLAT® for short—that give off the scent of female moths ready to mate.

The males can’t tell the difference between the pheromone plume emanating from the SPLAT versus the real thing—and many die before they are able to home in on a real partner.

“We throw a wrench into their communication system with lots of false plumes. In essence, it’s moth birth control,” explains Steffan MS’97, a CALS professor of entomology and a USDA entomologist.

Wisconsin is the nation’s leading producer of cranberries, growing more than all other states combined. Insect pests are a perennial problem, and while growers have insecticide sprays that largely do the job, notes Steffan, there’s room for improvement—especially in the interest of saving pollinators such as the honeybee.

“One of the typical spray-timings for the cranberry fruitworm is when the adult moths are flying, which is right during bloom when the honeybees are out,” explains Steffan. “That’s one of the huge drivers behind pheromone-based mating disruption—to avoid spraying when pollinators are active.”

In addition to such environmental benefits, this approach could also have a major impact on growers’ bottom lines. With growers doing fewer pesticide applications, the state’s cranberries should have an easier time entering European and Asian markets, which have stricter rules about pesticide residue levels.

“Wisconsin fruit has sometimes failed to meet those standards,” says Steffan, “but mating disruption is poised to change that.”

Growers of all stripes are eager to get their hands on this new option, including organic growers, who need more pest control options. “This will give them a powerful new tool,” says Steffan.

To speed things along, Steffan and his team are hard at work trying to mechanize the application of SPLAT. They are particularly excited about the potential of unmanned aerial vehicles (UAVs, better known as drones) and are working with Brian Luck, a CALS/UW–Extension professor of biological systems engineering, to build the perfect UAV for the job.

Steffan’s team is also exploring reformulating the SPLAT recipe. It currently works against two of the state’s top three cranberry pests: the aforementioned cranberry fruitworm and the blackheaded fireworm. But they want to go for the trifecta by adding the pheromone for the sparganathis fruitworm.

“I think this would be the first-ever three-species mating disruption blend,” says Steffan. “That’s what I dream about.”

PHOTO: Entomologist Shawn Steffan poses with SPLAT (in beaker) and a UAV—but the UAVs to be used in SPLAT application, now being built in partnership with BSE professor Brian Luck, will be bigger and better. (Photo by Joan Fischer/UW-Madison CALS)

The MBA of Dairy

The average age of a Wisconsin farmer is over 56 and rising, and the state has been losing around 500 dairy farms per year. It’s no surprise, then, that experts say it’s critical to prepare young people to step into farm roles in order to keep the state’s $88 billion agricultural economy strong into the future.

But making the transition into dairy farming is complicated, and aspiring farmers often don’t have the capital or the experience to take over an established operation.

Enter the Dairy Grazing Apprenticeship (DGA) program, which is working to address the issue by providing support for young people interested in becoming dairy farmers. Started in 2010, the first-of-its-kind program is administered by the Wisconsin-based nonprofit GrassWorks, Inc., with CALS as a key partner.

Earlier this year, DGA received $750,000 from the U.S. Department of Agriculture’s Beginning Farmer and Rancher Development Program. The funding will enable organizers to improve and expand the program in Wisconsin, as well as explore the possibility of rolling it out to other dairy states.

“It’s a meat-and-potatoes program that really takes people up to the level where they can own and operate their own dairy,” says DGA director Joe Tomandl. “It’s the MBA of dairy.”

Program participants complete 4,000 hours of paid training over two years, most of it alongside experienced dairy farmers, and work their way up from apprentices to Journey Dairy Graziers and Master Dairy Graziers. Although most of that time is spent in on-the-job training, there’s also a significant requirement for related instruction. That’s where CALS comes in.

As part of the program, apprentices attend a seminar about pasture-based dairy and livestock through the Wisconsin School for Beginning Dairy and Livestock Farmers (WSBDF), which is co-sponsored by the CALS-based Center for Integrated Agricultural Systems and the Farm and Industry Short Course. The seminar involves a 32-hour commitment, which is generally fulfilled through distance education and includes instruction from CALS professors from dairy, animal and soil sciences.

“We believe in the Wisconsin Idea and want to make sure our classes are accessible to people who want more education, but preferably close to where they live and work,” says Nadia Alber, a WSBDF outreach coordinator who helps organize the seminar and also serves on the DGA board.

In 2009, GrassWorks, Inc. turned to WSBDF director Dick Cates PhD’83 for guidance and access to a well-respected educational curriculum to help get the DGA up and running—and the WSBDF team has been involved ever since.

“We were just this little nonprofit with a very small budget trying to compete for a big federal grant,” says Tomandl. “For us, it was important to have UW–Madison as a strategic partner.”

As part of the most recent round of funding, DGA’s partners at CALS will lead an effort to quantify the program’s broader impacts.
“They have already proven that participants are moving along to their own farms after the apprenticeship, so they have an established track record,” says Alber. “This new study will look at some of the program’s other impacts, including economic, environmental and social.”

Turning them on

CALS biochemistry professor Hazel Holden is excited about science. So when she witnessed science becoming “boring” in her daughter’s classroom—a feeling several classmates shared—she decided to take matters into her own hands.

Some five years ago she created Project CRYSTAL—Colleagues Researching with Young Scientists, Teaching and Learning—a program designed to challenge middle schoolers who show an aptitude for science. The program is funded by the National Science Foundation.

Each school year, Holden takes four eighthgrade students under her wing for weekly hands-on sessions. “We’re trying to de-stigmatize science by exposing kids to material they otherwise would never have been exposed to,” she says.

And it’s impressive stuff. The students start by extracting DNA from yeast cells they have grown themselves. They then use the extracted DNA to practice the art of polymerase chain reaction (PCR for short), the process by which a piece of DNA is replicated to produce thousands to millions of copies of a targeted DNA sequence.

Switching between 10-minute lecture and lab segments keeps the kids motivated, and with clever anecdotes sprinkled throughout the lecture material, the young students are never bored.

This class format is used to progress to more advanced skills such as protein purification—the isolation of proteins from, in this case, E. coli cells— and X-ray crystallography, a tool used by the students to identify the molecular structure of a crystalline protein. The year ends with a group poster presentation— a rite of passage that most students don’t experience until much later.

“I was able to work in a real lab and gain lab experience. I do not think many 12-year-olds are able to have an experience like that,” says Project CRYSTAL alumna Manpreet Kaur, now a high school senior. “Before the program I did not have any knowledge of X-ray crystallography, and now I am able to explain the process in science classes.”

The program inspired Kaur to take several AP Science classes and affirmed her plans to become a doctor.

Holden has published her curriculum as an 80-page book, and Project CRYSTAL was introduced at Indiana University–Purdue University Indianapolis during the current school year.

The program has benefited graduate students almost as much as the youngsters, giving them experience teaching complex science at the most basic level.

“This class puts our own graduate work in perspective. You get more excited about your own research by watching them get excited about the small things, like pipetting,” reflects biochemistry doctoral student Ari Salinger.

Looking ahead, Holden hopes that what she has created will inspire other universities to implement similar programs.

“The students want to learn more—and they are ready for it,” Holden says.

Hello, Sweet-tart!

Two big players in Wisconsin’s food world are now an item. They were introduced at a CALS anniversary party earlier this year and are now sought-after for all the best campus events. We’re talking about Happy Cranniversary, the harmonious blend of vanilla ice cream and cranberry that the Babcock Hall dairy plant created in honor of CALS’ 125th anniversary.

A lot of people helped arrange this marriage. The name and basic idea came from Allison Dungan, an outreach specialist in the CALS soil science depart- ment who submitted the winning entry in a “name the anniversary ice cream” contest that drew 434 contenders. Concocting the flavor was the job of

Bill Klein, manager of the Babcock dairy plant, and research intern Sandy Hughes.

Klein knows a thing or two about inventing ice cream flavors—he’s developed dozens of great ones— but in this case he decided to get some help with the key ingredient. He turned to Marcy Berlyn, co-owner of Rubi Reds, a firm in Wisconsin Rapids that has found ways to incorporate cranberries into pretty much every food group, from trail mix, honey, vin- egar and mustard to bratwurst, cheese, wine, vodka and many more.

“Rubi Reds sent us a total of 10 to 15 different ingredient samples to evaluate,” says Klein. “We tested syrups in the basic ice cream mix until we found the intensity and type we were after. We then hand-mixed different variegates into the ice cream and evaluated for flavor and viscosity.”

The final product has three cranberry ingredi- ents: a syrup for flavor, a thicker, sauce-like “var- iegate” to form cranberry swirls, and sweetened cranberries.

Happy Cranniversary is a perfect union, mingling sweet and smooth with tart and chewy. It’s been a
big seller in the Babcock Dairy Store and at both UW student unions—and of course it’s been a hit in cranberry country. Rubi Reds has sold it by the scoop at outdoor events and by the carton at its retail store.

“We’ve made multiple runs to Madison to restock,” Berlyn says. “It’s a very popular product. We all love it.”

Five things everyone should know about gluten

1. What is it? Gluten is a substance composed of two proteins—gliadin and glutenin—that are found in the endosperm (inner part of a grain) of wheat, rye, barley and foods made with those grains, meaning that gluten is widespread in a typical American diet.

2. Is it harmful? People who suffer from celiac disease, an autoimmune digestive disorder, are unable to tolerate gluten. Even a small amount of it (50 milligrams) can trigger an immune response that damages the small intestine, preventing absorption of vital nutrients and potentially leading to other problems such as osteoporosis, infertility, nerve damage and seizures.

3. How widespread is celiac disease? An estimated 1.8 million Americans have celiac disease; as many as 83 percent of those suffering from it remain undiagnosed or are misdiagnosed with other conditions. Another 18 million (about 6 percent of the population) do not have celiac disease but suffer from gluten sensitivity. They report such symptoms as diarrhea, constipation, bloating and abdominal pain—which also are symptoms of celiac disease—but do not experience the same intestinal damage. For those with celiac disease or gluten intolerance, a gluten-free diet is beneficial.

4. Should you cut gluten from your diet even if you don’t have these conditions? Probably not. Restriction of wheat in the diet often results in a decrease in the intake of fiber at a time when most Americans consume significantly less than the recommended amount. Low-fiber diets are associated with increased risk of several acute gastrointestinal diseases (examples: constipation, diverticulosis) and chronic diseases such as heart disease and colon cancer. If not done carefully, gluten-free diets also tend to be low in a number of vitamins and minerals.

5. Don’t diagnose yourself. The broad range of symptoms associated with celiac disease and gluten sensitivity may be due to other causes; self-diagnosis and treatment of perceived gluten intolerance may delay someone from seeking more appropriate medical care. The only way to know for certain if you have celiac disease is from a blood test for the presence of specific antibodies followed by a biopsy of the small intestine. If you are experiencing the symptoms described above, please seek medical care.

Beth Olson is a professor of nutritional sciences. Her principal research areas concern breastfeeding support and improving infant feeding practices in low-income families.

Looking for “Hotspots”

In their quest to make cellulosic biofuel a viable energy option, many researchers are looking to marginal lands—those unsuitable for growing food—as potential real estate for bioenergy crops.

But what do farmers think of that? Brad Barham, a CALS/UW-Extension professor of agricultural and applied economics and a researcher with the Great Lakes Bioenergy Research Center (GLBRC), took the logical next step and asked them.

Fewer than 30 percent were willing to grow nonedible cellulosic biofuel feedstocks—such as perennial grasses and short-rotation trees—on their marginal lands for a range of prices, Barham and his team found after analyzing responses from 300 farmers in southwestern Wisconsin.

“Previous work in the area of marginal lands for bioenergy has been based primarily on the landscape’s suitability, without much research on its economic viability,” says Barham, who sent out the survey in 2011. “What’s in play is how much farmers are willing to change their land-use behavior.”

Barham’s results are a testament to the complex reality of implementing commercial cellulosic biofuel systems. Despite the minority of positive responses, researchers found that there were some clusters—or “hotspots”—of farmers who showed favorable attitudes toward use of marginal land for bioenergy.

These hotspots could be a window of opportunity for bioenergy researchers since they indicate areas where feedstocks could be grown more continuously.

“People envision bioenergy crops being blanketed across the landscape,” says Barham, “but if it’s five percent of the crops being harvested from this farm here, and 10 percent from that farm there, it’s going to be too costly to collect and aggregate the biomass relative to the value of the energy you get from it.

“If we want concentrated bioenergy production, that means looking for hotspots where people have favorable attitudes toward crops that can improve the environmental effects associated with energy decisions,” Barham notes.

CALS agronomy professor Randy Jackson is also interested in the idea of bioenergy hotspots. Jackson, who co-leads the GLBRC’s area of research focusing on sustainability, says that just because lands are too wet, too rocky or too eroded to farm traditionally doesn’t mean they aren’t valuable.

“The first thing we can say about marginal lands is that ‘marginal’ is a relative term,” says Jackson. Such lands have a social as well as a biophysical definition. “This land is where the owners like to hunt, for example.”

The goal of GLBRC researchers like Barham and Jackson is to integrate the environmental impacts of different cropping systems with economic forces and social drivers.

The environmental benefits of cellulosic biofuel feedstocks such as perennial grasses are significant. In addition to providing a versatile starting material for ethanol and other advanced biofuels, grasses do not compete with food crops and require little or no fertilizer or pesticides. Unlike annual crops like corn, which must be replanted each year, perennials can remain in the soil for more than a decade, conferring important ecosystem services like erosion protection and wildlife habitat.

The ecosystem services, bioenergy potential and social values that influence how we utilize and define marginal land make it difficult to predict the outcomes of planting one type of crop versus another. To tackle that problem, Jackson is working with other UW–Madison experts who are developing computer-based simulation tools in projects funded by the GLBRC and a Sun Grant from the U.S. Department of Energy.

Jackson hopes that these modeling tools will help researchers pinpoint where farmer willingness hotspots overlap with regions that could benefit disproportionately from the ecosystem services that perennial bioenergy feedstocks have to offer.

“These models will include data layers for geography, crop yield, land use, carbon sequestration and farmer willingness to participate,” says Jackson. “There could be as many as 40 data layers feeding into these models so that you can see what would happen to each variable if, say, you were to plant the entire landscape with switchgrass.”

Meat, With a Touch of Fruit

When Jeff Sindelar talks about the ingredients he’s working with, you’d think he was making juice. Not quite. He’s adding things like cranberry concentrate, cherry powder, lemon extract and celery powder to meat.

But Sindelar, a CALS professor of animal sciences and a UW–Extension meat specialist, is not adding them for flavor. He’s looking at ways to ensure that meat products labeled “organic” and “natural” are safe to eat.

Sales of organic and natural foods are booming, with double-digit percentage gains almost every year. As more and more food processors scramble to meet that demand, they’re encountering a special challenge. Because they must process these meats according to organic and natural label requirements, they are unable to use the vast majority of antimicrobial agents employed in standard meat processing.

“Most ingredients and technologies that serve as antimicrobials—ingredients that can improve safety by either suppressing, inhibiting or destroying any pathogenic bacteria—are not able to be used in products labeled ‘natural’ and ‘organic,’” Sindelar says.

The trick is to find alternative materials and processes that deliver safety—and also offer the look and flavor that consumers value.

Sindelar has identified some options. “A number of different natural-based organic acids offer a significant improvement to food safety,” says Sindelar, who is working in partnership with Kathy Glass, associate director of the CALS-based Food Research Institute. “We have tested a number of different ingredients such as cranberry concentrate, grape seed oil and tea tree extract.”

Some compounds from natural sources work as well as such standard preservatives as sodium nitrite, sodium lactate or sodium diacetate, to name a few. But it can take heavy doses of some natural ingredients to provide equivalent results—causing some undesirable side effects.

“Cranberry concentrate is a very effective natural antimicrobial,” says Sindelar. “But if you use the amount needed to significantly control the growth of bacteria, the meat turns cranberry red.”

Part of the researchers’ work involves “challenge testing”—adding pathogenic microbes to the meat to make sure that a given ingredient prevents the growth of bacteria throughout processing and storage. If substantial numbers of microbes grow, that ingredient is ruled out as being an effective natural antimicrobial.

Successful tests have already led to new products. Cherry powder combined with celery powder, for example, “is already being adopted by processors because of how effective these ingredients are in improving meat safety and quality,” notes Sindelar. And the search for other natural additives continues.

Both researchers are certain they’ll find success—particularly as they continue working in partnership with producers in the field.

“Collaborative research between the university and industry is essential to understand the synergistic effects of these ingredients—and to ensure the safety and quality of natural and organic meats,” says Glass.

Wisconsin’s “Brown Gold” Rush

Earth’s petroleum stores are dwindling, but a Wisconsin project aims to produce energy from a resource that’s in little danger of running low: cow manure, or “brown gold.”

The University of Wisconsin–Madison and several state companies, funded by a $7 million grant from the USDA Biomass Research and Development Initiative (BRDI), have partnered to pilot the conversion of dairy farm manure into useful product streams—a project that is expected to have significant environmental and economic benefits.

The Accelerated Renewable Energy (ARE) project is in progress at the 5,000-cow Maple Leaf Dairy in Manitowoc County, where animal waste is separated into different streams, or fractions, of processed manure.

After small plant fibers in the manure are separated and anaerobically digested to biogas, liquids from the digestion process are used to fertilize crops, while solids can be converted into useful chemicals and bio-plastics. Larger plant fibers make great animal bedding and mulch, not to mention a starting material for ethanol fermentation.

Meanwhile, at the new Wisconsin Energy Institute at UW–Madison, project co-investigator Troy Runge, a CALS professor of biological systems engineering, is analyzing the ARE project’s separation techniques to improve their efficiency. “We are performing many of the same separations that occur on the farm, but in the controlled environment of
the lab to both measure and optimize the system,” says Runge.

Tom Cox, a project collaborator and a CALS professor of agricultural economics, sees great potential for the initiative. “This is a triple-win situation; we would like to make money by doing the right thing by the environment and society,” he says.

Aicardo Roa-Espinosa MS’85 PhD’89, president of partner SoilNet LLC and an adjunct faculty member in biological systems engineering, developed the manure separation technology behind the project. Roa-Espinosa and Runge will monitor the quality, quantity and composition of biogas produced and analyze processed manure streams to identify chemical constituents. Student researchers will conduct life cycle assessments to evaluate the project’s environmental impact.

The goal for the four-year grant, researchers say, is to improve these manure separation technologies until their sustainability benefits can be realized on a broader commercial scale.

Runge notes that the public-private, multidisciplinary project exemplifies what the university hopes to do with the Wisconsin Energy Institute. “It’s also an example of a project that’s important to Wisconsin,” he says.

Indeed, the project may help farmers manage manure with benefits for both the environment and human health. A 5,000-cow dairy farm like Maple Leaf produces approximately 25 tons of manure per day, which require millions of gallons of water to manage. Although some manure may be used as fertilizer, nutrient imbalances and runoff can create environmental problems. However, manure processed using SoilNet’s technology yields concentrated, homogenized fertilizer that can be applied with greater control over nutrient content.

In addition to its environmental benefits, the cellulosic—or non-food—plant biomass derived from dairy manure avoids the conflict of “food versus fuel.”

That’s a promising basis for exciting innovations at dairy farms. For ARE project leaders, farms are not only the heart of agriculture. They also have the potential to serve as foundations for cellulosic biorefineries that could prove key in supporting a local green economy and a sustainable energy system throughout the region.