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Oregon State University Agricultural Research updates

Fresh-peeled pears, anyone?

Pear fans may soon buy their favorite fruit peeled, sliced and ready to eat from the supermarket.

The challenge is to keep the same fresh taste and texture the fruit had when first peeled and sliced up two weeks before.

Oregon State University researchers have identified treatments for fresh-sliced pears that will inhibit pear browning and textural deterioration. They have also learned what causes pears to deteriorate, which will help in the development of a more consumer-friendly product.

Peeling a pear.

Finding a way to keep peeled, sliced pears fresh is challenging, scientists say. Photo: Lynn Ketchum

"The pear is a challenge compared to, say, the apple," said David Sugar, a plant pathologist at OSU's Southern Oregon Experiment Station at Medford. "The pear has a narrow window of eating ripeness."

Sugar, graduate student Xiaoling Dong and OSU food scientist Ron Wrolstad have been studying pear behavior to see what treatments would keep pears fresh the longest.

"First, we're trying to identify the proper moment of maturity-when a pear should be sliced," Sugar said. "Then we want to see what inhibits browning and textural deterioration."

The scientists have found a variety of treatments that will inhibit browning and deterioration of fruits. In apples, for example, ascorbic acid (vitamin C) works very well. However, ascorbic acid would only keep pears fresh five to seven days.

"We continue to look at a range of materials that keep pears fresh longer, and we think we've found an excellent prospect," Sugar said.

The winner is 4-hexylresorcinal, currently used to keep fresh shrimp pink and an ingredient in throat lozenges. The chemical does not have FDA approval for fruit, but a manufacturer is considering pursuing that approval.

"Our research shows 4-hexylresorcinal can keep pears from browning for 30 days or more," Sugar said.

Another ingredient, he said, is calcium lactate. "This compound has already received FDA approval, is safe to use and enhances the ability of sliced pears to retain their firmness and texture," Sugar said.

Even with the chemicals, keeping pears fresh will require special treatment-what Sugar calls "keeping the cool chain."

"Pears will be more work than dipping them in vitamin C," Sugar said. "We'll have to keep them cool from manufacturer to consumer. The slicing will be done in a cold room, packages will be stored in a cold room. The pears will be shipped in a cold truck to a refrigerated distribution center, then sent to a grocer's refrigerated shelf."

Don't ruffle your feathers, Einstein

There's no way to scientifically prove animal intelligence, but Steve Davis is sure animals on the farm have minds and can think.

Most of his fellow faculty and graduate students at Oregon State University agree, although nobody gives rocket scientist status to a chicken or turkey.

Illustration of a cross-eyed chicken looking at a chalkboard with 2+2=5 written on it.

Illustration: Tom Weeks

In a paper presented at the annual meeting of the American Society of Animal Science, Davis reported that more than 80 percent of those he surveyed believed animals have minds and can think.

"As for myself," Davis said, "I subscribe to the Charles Darwin theory that animal minds differ from human minds only in degree, not in kind. In that regard, I disagree with some of today's scientists who endorse Darwin's theory of evolution, but don't support his idea that animals are evolving both physically and mentally."

The animal scientist conducted the survey of people's perception of animal intelligence with OSU colleague Peter Cheeke. Those surveyed included faculty and graduate students in animal science, zoology, veterinary medicine, English and philosophy, plus members of the Oregon branch of the American Association of Laboratory Animal Sciences, who are in charge of university research animals.

The faculty and students surveyed gave the highest marks to their pets. They ranked the dog and cat as most intelligent with the pig and horse close behind. Next came the cow and sheep. Last, in a dead heat, were the chicken and turkey.

"There were really no differences between the groups of respondents and their perceptions of relative intelligence," Davis said. "Regardless of profession or educational background, rankings of intelligence came out remarkably alike."

Respondents were asked to assign a number to the different species with 1 being highest intelligence and 5 being the lowest. Overall, dogs earned a 2.1 ranking and cats 2.3. The pig and horse were tied at 2.6.

The animal science faculty and students and veterinary medicine faculty rated the cat and pig even. Philosophy faculty rated the pig smarter than the cat. "Maybe they have pot-bellied pigs as pets, or maybe they've seen the movie 'Babe,'" Davis theorized.

Ranked at the bottom in perceived intelligence were the cow (3.2), the sheep (3.5), and the chicken and turkey (both at 4.0).

Davis said the concept of animal minds and intelligence is central to the Animal Protection Movement.

"At one end of the movement are animal rightists who virtually say humans shouldn't use animals for any purpose," Davis said. "At the other end are those who say God has given men dominion over all the animals, and therefore we can use them anyway we want.

"People join one camp or another based on their perceptions. Animal agriculture needs to be paying attention to those perceptions. The more we know about perceptions and animal intelligence, the more humanely animals will be treated."

Davis said those with different philosophies will probably interpret the survey data differently, depending on their biases.

"For most, the data support a continuation of the status quo in animal agriculture-but only so long as the animals are treated in accord with their intelligence," he said. "However, many respondents, including animal scientists and veterinarians, believe some production confinement systems are not humane."

He said scientists have been unsuccessful in measuring absolute animal intelligence.

"Behavioral scientists may say every animal is smartest for its own ecological niche," he explained. "The limitation in measuring cross-species intelligence is the inadequate tools for assessment we have available. Standard methods of assessment may show one species to be smarter on one test than another species, but a different method might show just the opposite."

Those surveyed were asked, "Does (species) difference in mental capability have any bearing on our responsibilities to them?"

"Some said no, because we have a duty to treat all animals with respect, regardless of their intelligence-that we should respect their needs and treat them humanely," Davis said.

"Some said yes, because the more intelligent species require different management to keep these animals from becoming bored.

"Others said yes, because we have to take especially good care of the stupid ones or they could panic in response to stress and hurt themselves."

Davis was raised on a farm in Idaho. In addition to crops, his family raised dairy cows, horses, pigs and chickens.

"When I was young, I thought, 'Animals probably have minds, but mostly they react out of instinct.' I've changed since then. Now I believe animals do think. They do apply a certain amount of logic in problem solving. But they are different from humans in that they don't have the depth of intelligence."

Davis said the questions of animal intelligence were meant to be serious. Still, he had to wonder what his colleagues thought of the whole business. So, on the questionnaire to animal science faculty only, they added one last question: "Do you think Davis and Cheeke have really gone over the edge on this one?"

"I shouldn't admit this," Davis said, "but about half said yes!"

Native grasses touted for restoration work

After screening candidates for more than a decade, plant researchers have singled out two populations of blue wild rye, a native grass found throughout the western United States, as excellent choices for use in revegetation and erosion control in the Pacific Northwest.

They have named the two populations, which scientists call ecotypes, "Arlington" and "Elkton" for Arlington, Wash., and Elkton, Ore., towns nearest to where the original genetic material was collected.

Arlington was developed by the U.S. Department of Agriculture's Natural Resources Conservation Service (NRCS), the Oregon State University Agricultural Experiment Station and Washington State University's Agricultural Research Center. Elkton was developed by the NRCS and OSU's Agricultural Experiment Station.

A grassy hillside.

Arlington blue wild rye established on what was a bare forest hilside. Photo: Dale Darris

"We began comparing 128 populations collected from all over western Oregon, western Washington and adjacent areas back in the early 1980s," said Dale Darris, a conservation agronomist for the NRCS's Plant Materials Center at Corvallis, Oregon.

"The best eight of those were grown in solid stands and further tested for their agronomic performance and maturity differences," he said. "Final evaluations occurred on logging roads, clearcuts and other upland revegetation sites.

"Both grow well and provide erosion control around wooded areas, particularly those sites that have been recently disturbed by fire, logging or road work," Darris added.

Arlington is especially recommended for the Puget lowlands of western Washington, where it originated. But the grass also has performed well at low elevations in western Oregon, according to Darris.

Elkton is recommended for western Oregon and northwestern California, below an elevation of 2,000 feet.

"Both are tall, erect, medium-coarse, loosely tufted ecotypes of blue wild rye compatible with trees growing in woodlots or along the upper banks of streams and riparian zones," said Darris.

Blue wild rye (Elymus glaucus) will take full sun to intermediate shade and grows well in a woodlot where the tree canopy has not completely closed, he noted. Or it can be used as quick, self-perpetuating cover for erosion control on roadsides or site rehabilitation on burned or cut-over timberland.

Other potential uses for blue wild rye include enhancing wildlife habitat and adding diversity to native plantings, he said. Before maturity, the native grass is considered fair to good forage for cattle, horses, deer and elk, but poor for sheep. However, the specific palatability and nutritional value of Arlington and Elkton for livestock are not fully established, Darris said.

Arlington and Elkton are short-lived (4 to 6 years) perennials. Arlington has a blue-green appearance and a white waxy coating on the stems. Elkton is grass green, lacks any waxy coating and matures 9 to 14 days earlier than Arlington. It also greens up at least a month earlier in the spring.

Darris said both do best on well-drained to somewhat poorly drained soil that is moderately coarse to fine textured. Annual rainfall should be more than 25 inches.

"Arlington and Elkton are not necessarily intended to replace local, on-site sources of blue wild rye if such seed is available," Darris said, "especially for ecological restoration plantings."

The recommended drilled seeding rate with Arlington and Elkton for most uses is 10 pounds per acre, he noted.

Certified seed of Arlington blue wild rye is commercially available to the public from seed vendors. Limited quantities of breeder and foundation seed of Elkton and Arlington are available to qualified growers, according to Darris.

For more information on where to obtain seed and how to produce or use the two grasses, contact Darris at the NRCS Plant Materials Center, 3415 NE Granger Ave., Corvallis, Ore., 97330, or Scott Lambert, plant resource specialist, NRCS, Washington State University, P.O. Box 646410, Pullman, Wash., 99164-6410.

Researcher eyes cherry "Gasohol'

It may come as no surprise, but maraschino cherries don't grow on trees. Well, the fruit does, but the process that turns them into sweet, red treats involves "brining."

A silver bowl of maraschino cherries.

Oregon produces almost half the country's brined cherries, including maraschinos like these. Photo: Lynn Ketchum

Oregon produces 30 to 40 percent of all U.S. brined cherries which include, but are not limited to, maraschinos. These cherries bring Oregon briners 90 cents to $1 per pound. The cost of disposing of the brine eats up about three cents for every pound of brined cherries sold.

That adds up. There are about 10 million gallons of brine leftover in Oregon each year. It can't just be flushed down the drain, and the annual cost of treatment and disposal-primarily in Salem and The Dalles-is about $900,000.

Carl Payne, head of research and development for Oregon Cherry Growers, Inc., says he started looking for alternative methods of disposal several years ago when he attended a food technology presentation by Oregon State University food scientist Alan Bakalinsky. Bakalinsky recommended fermenting the brine to extract ethanol and designed an experiment to see if that was feasible.

Ethanol is commonly used as a partial gasoline replacement (sometimes called "gasohol"). Brazil has even tried to convert its cars to run on pure ethanol.

"Just about anything with sugar content can be fermented, but most of the ethanol in the U.S. comes from corn sugar and is produced on a huge scale," said Bakalinsky.

Small-scale tests have been completed and Bakalinsky estimates cherry briners could produce 260,000 gallons of pure ethanol from brine each year.

"This a very small amount and alone would never justify construction of a fuel ethanol plant," he said. "But if combined with other locally generated food processing wastes that contain sugar, an ethanol distilling business might become a practical alternative to disposal in Oregon. However, the economics of trucking food processing wastes, and the relatively low prices of oil compared to ethanol, make this unlikely in the near future."

Bakalinsky says there might be a way to squeeze a few more cents out of the distillation. There are other recoverable byproducts of the process, such as benzaldehyde, a key cherry flavoring agent, and calcium sulfite, which may have value as a liming agent to reduce the acidity of Oregon's soils.

"We're keeping distilling on our short list of alternatives," Payne says, "but right now it is still cheaper to pay to treat and dispose of the brine than to distill out the ethanol. The main economic hitch remains transportation costs. We would have to either build two distilling operations or truck the brine from The Dalles to Salem or vice versa. The same holds true for using a third-party distiller. The cost of trucking the brine, which is 95 percent water, isn't cost effective."

Bakalinsky says the whole economic picture could change rapidly if the price of oil rises, making ethanol more valuable, or if the costs of brine disposal go up.

Yew could grow it at home

The raw material for an FDA-approved cancer treatment could be grown in your front yard, an experiment at Oregon State University's Malheur Experiment Station near Ontario suggests.

OSU and University of Portland researchers are studying landscape plants that produce Taxol, one of the most promising treatments for breast and ovarian cancer.

Taxol is the trade name for a drug first extracted from the bark of the Pacific yew tree and marketed by Bristol-Myers Squibb. Early on, this practice led to fears that the slow-growing trees would be decimated for the drug.

"Reports of people pillaging the forests for Pacific yew bark to sell to pharmaceutical companies are probably more urban legend than truth," said Angela Hoffman, a chemistry professor at the University of Portland. "However, whether the bark is being taken legally or illegally, it is an unsustainable and apparently unnecessary practice. It looks like we could produce all the Taxol we need from leaves harvested from just a few well-managed plantations.

"Taxol, also known as paclitaxel, may actually be as plentiful in the leaves as the bark of the Pacific yew. We have also found paclitaxel in the leaves of several landscaping yews," said Hoffman.

Where and how to grow landscape-type yews is under study at OSU's Malheur Experiment Station on the Oregon-Idaho border.

Man kneeling next to young yew trees.

The leaves of landscape-type yews like these Clint Shock is growing at OSU's Ontario experiment station contain taxol, the anti-cancer substance. Photo: Dennis Hinkamp

"The experiment is in its second year and looks promising," said Clint Shock, superintendent of the branch experiment station, who is collaborating with Hoffman. "The plant we're working with is Taxus media hicksii, a hybrid of the wild tree with a domesticated plant."

The OSU agronomist had a hunch water stress might increase the paclitaxel content of yew leaves. It turned out he was right.

"Although the purpose paclitaxel serves in plant physiology is unclear, we do know that its levels increase when the plant is stressed," he said. "We're running trials of varying levels of water consumption and finding a 40 percent increase when the plants are deprived of water to the point where it stresses them, but still allows them to grow."

Hoffman analyzes the leaves grown at the OSU station. She says Shock's experimental plots are producing about 90­130 micrograms of paclitaxel per gram dry weight of yew leaves.

To put that into perspective, she explains that it takes about 200 micrograms per cancer treatment and patients generally receive 8­12 treatments over a several-week period. Currently only approved for breast and ovarian cancer treatment, Taxol also is being tested in combination with other cancer drugs.

Producing Taxol from yew leaves looks to be sustainable and cost effective, Hoffman said. Three research groups have made synthetic Taxol in the laboratory, she noted, but the process currently is far too expensive and labor intensive to meet the demand.

"We still need to look at the overall economics of growing yews," she said. "On the western side of Oregon they grow faster but contain less paclitaxel per leaf. On the eastern side they grow slower, but the limited rainfall there makes it easier to create water stress, thus increasing (paclitaxel) concentration."

Agent plants scavenger in Willamette cornfields

Driving through the Willamette Valley last summer you may have noticed dairy farms with corn that looks like it was planted in a lawn. Mike Gangwer did that.

Man working in a cornfield.

Marion County extension agent Mike Gangwer plants grass in a corn field. The practive can combat pollution while boosting income. Photo: Lee Ko

The Oregon State University extension dairy specialist planted ryegrass in the cornfields. The ryegrass helps take the stink out of manure and prevents water quality people from raising a stink about manure runoff into streams or underground water supply.

Gangwer is Marion County dairy extension agent and the dairy specialist for the 160 dairy farmers in the eight Willamette Valley counties. Aboard his Honda four-track, he became the Johnny Appleseed of "relay cropping," seeding more than 255 acres of cornfields to ryegrass.

"Relay cropping" means planting annual ryegrasses anywhere from corn planting time up until the corn is 18 inches tall. After the corn is harvested, the ryegrass remains to sponge up any liquid manure the dairy producer sprays on the land during winter.

The cover crop of ryegrass also reduces soil erosion, giving the farmer a sod base instead of empty corn ground subject to nutrient runoff into streams or underground water supplies.

Also, the ryegrass will "scavenge nutrients" from the manure and from fertilizer left in the field after the corn harvest, Gangwer said. That makes the ryegrass a good source of feed for heifers and cows in spring.

"There are no losers when relay cropping with ryegrass-except the inorganic fertilizer salesman," Gangwer said. "Relay cropping helps soil stewardship, provides wildlife cover and safeguards water quality. It's good insurance for the producer who wants to stay in compliance with the federal Clean Water Act and Oregon Confined Animal Feeding Operation rules.

"In OSU experiments on these dairy farms, we found that the ryegrass removed 310 pounds of nitrogen per acre from the soil profile-nitrogen that could have leached into groundwater," he said.

Relay cropping has economic payoff, too. Ryegrass seed, which is plentiful in the Willamette Valley, costs only about $8 an acre.

"I've seeded up to 30 acres in five hours with my four-track," he said. "But farmers could use a spinner-spreader behind the corn planter and easily seed 120 acres a day."

Gangwer said fields will yield up to 5 tons of ryegrass dry matter an acre worth at least $100.