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Enjoy summer’s fruits and vegetables — safely

Now that we’re in the thick of summer and eating bountiful quantities of uncooked fresh fruits and vegetables (salads, and fruit bowls, and tomatoes — oh my!), it’s time to make sure we handle them properly to avoid foodborne illnesses.

According to Dr. Trevlor Suslow, a plant pathologist and Cooperative Extension specialist at UC Davis, “Americans consume more than six billion servings of uncooked fresh fruits and vegetables every year, versus a very small number of illnesses that are clearly linked to foodborne pathogens.”

The take-home message is that the food supply in the U.S. is generally very safe, particularly when everyone in the food supply chain (including consumers) does their part to assure food safety.

The U.S. Food and Drug Administration (FDA) recently released the following information for home consumers:

Nearly 48 million people (1 in 6 people) are sickened by food contaminated with harmful germs each year, and some of the causes might surprise you.

Although most people know animal products must be handled carefully to prevent illness, many don’t realize that produce can also be the culprit in foodborne illness. In recent years, the U.S. has had several outbreaks of illness caused by contaminated fruits and vegetables — including spinach, tomatoes, and lettuce.

Fresh produce can become contaminated in many ways. During the growing phase, fruits and veggies may be contaminated by animals, harmful substances in the soil or water, and poor worker hygiene. After produce is harvested, it passes through many hands, increasing the contamination risk. Contamination can even occur after the produce has been purchased, during food preparation, or through inadequate storage.

The FDA says to choose produce that isn’t bruised or damaged, and make sure that pre-cut items — such as bags of lettuce or watermelon slices — are either refrigerated or on ice both in the store and at home. In addition, follow these recommendations:

  1. Wash your hands for 20 seconds with water and soap before and after preparing fresh produce.
  2. Cut away any damaged or bruised areas before preparing or eating.
  3. Gently rub produce while holding under plain running water. There’s no need to use soap or a produce wash.
  4. Wash produce BEFORE you peel it, so dirt and bacteria aren’t transferred from the knife onto the fruit or vegetable.
  5. Use a clean vegetable brush to scrub firm produce, such as melons and cucumbers.
  6. Dry produce with a clean cloth or paper towel to further reduce bacteria that may be present.
  7. Throw away the outermost leaves of a head of lettuce or cabbage.

Store perishable produce in the refrigerator at 40 degrees or below.

(Condensed from an FDA news release. The site has an interesting video and useful links to other sites with food safety information.)

For more on what UC Davis and UC Cooperative Extension are doing to assure the safety of fresh produce:

Posted on Tuesday, July 12, 2011 at 5:35 PM

A fruitful approach

I have two active young sons. They get plenty of exercise. Their diets, however, can be a challenge. They have different tastes – one could eat breakfast items all day; the other could eat dinner items all day. One likes sugary sweet foods; the other likes salty, fatty foods. My wife is a great cook who makes balanced, nutritious meals, but it’s not easy pleasing everybody. There is one thing we all can agree on: We love fruit.

We can eat fruit throughout the day. It might go with breakfast, with lunch, as a snack or mixed in with a salad at dinner. I think my kids like fruit not only because we make it available and encourage them to eat it, but because they have sampled fresh fruit at farmers markets, watched it grow in our backyard and harvested it themselves at U-pick farms.

The federal government’s new MyPlate nutrition guidelines emphasize fruits and vegetables – they’re half the plate. But it’s not enough to try to force-feed your children canned carrots. Food can be fun. Giving kids a hands-on experience with fresh fruit can help them appreciate its importance. I’m no dietitian, but as a parent, I offer three tips for helping children to eat more fruits (and vegetables).



  1. Go to a farmers market. California has more farmers markets than any other state in the country. Find one near you at www.cafarmersmarkets.com. At a farmers market, the food and the farmers are the stars. You can sample the goods. You can ask a farmer questions. You can learn about the difference between a blood orange and a Cara Cara orange. It’s an event, but a short one. And the price is moderate.

  2. Grow your own produce. We’ve had mixed results with this one. Tomatoes came out great one year, were poached by animals another. We have a couple of fruit trees in our yard, but they don’t get much sun and the fruit isn’t sweet. We have had success with herbs, though, and find that our sons will munch on a mint leaf or point out the plants to friends and family. On a recent visit to their aunt and uncle’s house, they picked giant lemons and enjoyed homemade lemonade. No matter how small the effort, it shows children the life cycle of a plant, the anticipation of healthy food and, hopefully, the payoff of plentiful produce for a low cost.

  3. Visit a U-pick farm. We get an early start to summer by visiting U-pick farms in Brentwood. One son prefers cherries; the other prefers strawberries. Between the two, we have a daylong excursion that provides a weeklong supply of delicious bite-sized fruit for a reasonable price. Brentwood’s cherry season typically lasts from May to June. You can still find peaches, strawberries and other crops there in July. We also went apple picking in September in Sonoma County. U-picking is part of the broader field of agritourism, which also can include farm stands, tours, fairs and festivals. The University of California maintains a statewide agricultural tourism directory at http://calagtour.org. Check it out and may your efforts be fruitful.
Posted on Tuesday, July 5, 2011 at 11:33 PM
  • Author: Alec Rosenberg

New findings on benefits of “biofactors” in food

Can what we eat help fix what ails us? Research increasingly suggests the answer is “yes.” Many foods contain biofactors — biologically active compounds — that may prevent and treat illnesses including asthma, diabetes and heart disease, according to new studies from the UC Davis Center for Health and Nutrition Research (CHNR).

The upcoming July-September California Agriculture journal (to be posted by July 11) reports UC research into plant compounds (phytochemicals) that can help prevent or treat disease. The findings stem from pilot projects at the center, as well as other UC research. Articles focus on how micronutrients, biofactors and phytochemicals (plant compounds) can help reduce the risk of chronic diseases.

Kale is a rich source of omega-3 fatty acids.
Biofactors are compounds in our food that affect us at the biochemical level and may ultimately benefit our health. For example, the omega-3 fatty acids in foods such as walnuts, flax seeds, kale and salmon may protect against a range of diseases associated with inflammation, including asthma and the hypertension-related inflammation that can damage kidneys. CHNR research suggests that omega-3 fatty acids could reduce asthma symptoms as well as kidney damage.

Phytochemicals and health. Epidemiological studies link particular diets to less risk of chronic diseases. Notably, the traditional Mediterranean diet — mostly vegetables, fruits and whole grains, with moderate amounts of nuts, olive oil and red wine — is associated with lower rates of heart disease, cancer, and Parkinson's and Alzheimer's diseases. However, it has yet to be firmly established that specific phytochemicals in our diets can protect against diseases. Nutritionists therefore advise eating a wide variety of plant-based foods rather than taking supplements.

Walnuts are an important source of omega-3 fatty acids.
That said, a number of phytochemicals do show promise in protecting against and even treating chronic diseases. For example, research shows that soybeans contain estrogen-like compounds called isoflavones that may protect against heart disease, and that compounds in olive oil and red wine may protect against heart disease and diabetes.

Mitochondrial nutrients and aging. The Mediterranean diet is rich in plant compounds that boost mitochondria (organelles in our cells that convert glucose and other nutrients into energy) and so are known as mitochondrial nutrients. When mitochondria are scarce or have genetic defects that keep them from working properly, this can generate toxic metabolites and damaging free radicals.

“Mitochondria are central to aging,” says UC Irvine aging expert Edward Sharman. “Improving their function may modulate or delay the onset of diseases related to aging, such as type 2 diabetes and age-related macular degeneration.” Mitochondrial dysfunction also plays a key role in chronic illnesses such as heart disease, type 2 diabetes and inflammatory diseases such as arthritis.

Extra virgin olive oil contains hydroxytyrosol, an important nutrient for cellular mitochondria.
One of the most promising mitochondrial nutrients is hydroxytyrosol, which is abundant in the extra-virgin olive oil that provides most of the fat in the traditional Mediterranean diet. Moreover, the red wine that is integral to the Mediterranean diet also induces the body to produce more hydroxytyrosol.

A new essential nutrient? Another promising mitochondrial nutrient is pyrroloquinoline quinone (PQQ), which was first found in nitrogen-fixing soil bacteria and is now known to be ubiquitous.

“We’re exposed to PQQ all the time at low levels,” says CHNR co-director Robert Rucker, a UC Davis nutrition professor. “It can be derived from amino acids found in stellar dust, and stellar dust is what the earth is made of.”

While Escherichia coli and other common gut bacteria do not make PQQ, the soil bacteria provide it to the plants in our diet. Good sources include fermented soybeans, wine, tea and cocoa.

Animal studies show that PQQ affects health markedly. Rucker and his colleagues found that depriving rats of PQQ compromised their immune systems, and retarded their growth and reproductive rates. In contrast, restoring PQQ to their diets reversed these effects and returned them to good health. Moreover, PQQ stimulated nerve growth and counteracted aging in cultured cells.

Rucker and his colleagues found that, like hydroxytyrosol, PQQ increases the number of mitochondria in cells. “It’s also an extremely good antioxidant and anti-inflammatory agent,” he says.

Personalized medicine. Understanding what biofactors do in our bodies could ultimately lead to personalized medicine, where nutrition-based treatments are tailored to the particulars of each person’s biochemistry. This individual variation at the biochemical level may help explain the inconsistent outcomes of research on omega-3 fatty acids and inflammation.

“The studies are mixed,” says UC Davis pulmonologist Nicolas Kenyon. “Some have shown little effect and others have shown that omega-3 fatty acids can reduce arthritis and inflammation in blood vessels.”

One biochemical pathway leading to asthma may be counteracted by the omega-3 fatty acids in fish oil
Asthma can be caused by multiple biochemical pathways, which are series of chemical reactions in our cells that metabolize compounds into other products. One pathway leading to asthma may be counteracted by the omega-3 fatty acids in fish oil, and this pathway may be more active in some patients than in others. To identify those likely to benefit from omega-3 fatty acid treatment, Kenyon and his collaborators are genotyping asthma patients.

This genotyping is targeted to DNA sequences associated with asthma and so is not comprehensive.

“Some people are nervous about genome-wide analysis, which is scary because none of us is perfect,” Kenyon says. “But people are more interested when the focus is specific screening that could increase their chances of treatment.”

Posted on Tuesday, July 5, 2011 at 3:01 PM
  • Posted By: Janet L. White
  • Written by: Robin Meadows

Childhood obesity: Seeking solutions in San Diego

I recently switched from a small group practice to Kaiser when the rates for my old healthcare plan went up. My first visit to my new doctor was like something out of a happy-healthcare utopia: a farmer’s market out front hawked fresh peaches and plums; bright light streamed through tall windows as I found my way to a well-marked suite; a receptionist cheerily informed me there was no copay for this welcome visit.

But in my brief stay in the waiting room, I noticed there was an entire row of oversized chairs. And when I was ushered to the scale, in place of the typical stand with little black weights I found what can only be described as a freight scale — a large electronic platform at least 3 feet x 3 feet, built right into the floor.

The startling site of the industrial-strength scale brought home to me the severity of America’s obesity epidemic, and we are passing this problem on to our children to the extent that the First Lady Michelle Obama and the Surgeon General have both made childhood obesity one of their key public platforms.

The stats keep rolling in:

  • One out of three children born in 2000 are projected to become diabetic in their lifetime.
  • Heart disease risk factors now occur in one out of six children school-age kids.

Attendees at the Sixth Biennial Childhood Obesity Conference, convening this week in San Diego (June 28-30), will dig deep into the problems … and possible solutions.

Hot topics will include the newly released dietary guidelines: just last month the United States Department of Agriculture retired the pyramid in favor of a plate.

Patricia Crawford, a Cooperative Extension specialist and director of the UC Berkeley-based Atkins Center for Weight and Health (CWH), a co-sponsor of the conference, said the new guidelines are geared more towards obesity prevention, whereas in the past the focus was on making sure there were no nutrition gaps.

“The plate is very similar to one developed by California Cooperative Extension,” said Crawford. “California was an early adopter — along with New York City, the American Cancer Institute, Canada, and others."

Crawford said Cooperative Extension specialists and advisors tailored the plate concept to different ethnic groups.

“We realized early on that that the plate was a valuable teaching tool,” Crawford said.

The conference will also focus on the problem of junk-food advertisements targeting kids.

“Just last month the Federal Trade Commission came out with voluntary guidelines for industry,” said Crawford. "Public health advocates pushed for monitoring to see the degree to which marketing efforts change. This voluntary approach gives the industry a chance to change on their own before it’s mandated.”

Schools are taking the issue seriously, and California has been a leader for many years. Back in 2003 there was an unfunded mandate to replace profit-making junk food with better meals. Nothing happened.

Then in 2005, the Department of Education, with funding from Department of Agriculture, commissioned an evaluation to measure how much money schools will actually lose by removing the sales of cheap junk food. The CWH was the independent evaluator.

The finding? Surprise: most schools — over 80 percent — made more money when they got rid of those foods.

“It turned out that most money came from snacks. When kids quit buying junk, they moved to buying school meals, subsidized by the school meal program — and the profits came. In 2005 Governor Schwarzenegger signed legislation to limit high-sugar, high-fat snack foods in K-12 schools.

Crawford says more than half the states now have this type of legislation limiting these “competitive foods.”

Other hot topics in San Diego will be:

  • Are all calories created equal? Studies say quality matters as much as quantity.
  • National policy: Speakers address the Obama administration's unprecedented investment in prevention, and how it can be effective.
  • Sugar-loaded beverages: National experts will be talking about newest research on how the sweet stuff is contributing to obesity.

Conference attendees can be inspired by findings that all the work in California is beginning to have an impact.

In a recently published article, the CWH showed that California is slowing the overall rate of childhood obesity. Crawford notes that legislation in 2005 to limit sugars and fats in school lunches correlates directly with the time that rates began to go down. The changes were slight, but significant.

“An individual losing a half pound at Weight Watchers may not be news, but when it comes to populations, a tiny shift indicates a tremendous public health impact,” Crawford said.

However, she notes that the disparities are more pronounced: certain groups are going down, and other high-risk groups rates are going up.

“We are beginning to have some traction, but we need to keep it up,” Crawford said.

In addition to the Atkins Center, the conference is co-sponsored by the California Department of Public Health, the University of California, Berkeley, the California Endowment, and Kaiser Permanente.

Posted on Tuesday, June 28, 2011 at 3:14 PM
  • Author: Ann Brody Guy

Nothing plain about this UC Davis vanilla research

There is good news for those who are wild about all things vanilla – from ice cream to candy and even savory foods.

One of the world’s most popular flavors, vanilla comes from vanilla beans, which are grown in Madagascar, Mexico and other tropical regions. Unfortunately, vanilla farmers in these regions struggle to overcome low prices, a fungal disease epidemic, climate stress and environmental deterioration.

UC Davis scientist Sharman O’Neill is working to overcome some of these problems by carrying out genomic research to improve commercial vanilla plants and their sustainable cultivation in Madagascar.

Her efforts were recently recognized by the global food company General Mills, which named O’Neill the national winner of the General Mills Sustainability Challenge, a call for universities’ best ideas for reducing waste, encouraging sustainable consumption and using resources responsibly.

Pale green vanilla flower.

The honor comes with $200,000 to support the genomic vanilla research through O’Neill’s Vanilla Sustainability Project in UC Davis’ College of Biological Science.

The researchers aim to improve the genetic basis of the vanilla-bean crop so that vanilla farmers can overcome the problems posed by disease, climate stress, market uncertainties and environmental decline.

There is a lot at stake here because if these farmers abandon vanilla and change to other crops, the tropical forests, where the vanilla vines grow in compatible agroforestry systems, would likely be cut down. That would destabilize the critical habitat of innumerable plants and animals, including precious species of lemurs in northeastern Madagascar, the major vanilla-producing country.

"General Mills' goal is to maintain a strong, sustainable supply of high-quality vanilla beans," said Steve Peterson, director of sourcing sustainability at General Mills. "That's what this project is all about."

O’Neill’s vanilla research team involves an international group of scientists from the J. Craig Venter Institute in the United States; the French research center CIRAD on Réunion Island; the University of Antananarivo in Madagascar; the Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias /SAGARPA in Mexico; and other international collaborators.

As part of the project, the scientists plan to use cutting-edge genomic sequencing and mapping technologies, in combination with traditional plant-breeding methods, to develop improved and new vanilla varieties that are hardier, more disease-resistant and offer enhanced flavor. A separate element of the project will also advance efforts to promote a more equitable model for sustainable vanilla cultivation with General Mills’ business partners.

Posted on Friday, June 24, 2011 at 8:22 AM

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