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UC Food Safety

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Not so 'virgin' olive oil

Buyer beware, is the message of a new study from the UC Davis Olive Center, which found that many of the imported olive oils sold in California retail stores are not “extra virgin” oil as their labels claim they are.

Extra virgin olive oil is the top grade and priciest of olive oils.  To meet international standards, extra virgin must be removed from the olive without using heat or solvents.  It also has to meet specific criteria for chemical makeup, flavor and aroma.

However in the new study, researchers at UC Davis and in Australia discovered that 69 percent of the imported oils sampled, compared to just 10 percent of the California-produced oils sampled, failed to meet internationally accepted standards for extra virgin olive oil.

The imported oils tested were purchased from supermarkets and “big box” stores in three California regions: Sacramento, the San Francisco Bay Area and Los Angeles County. The California brands, however, were found only in the Sacramento and San Francisco Bay Area.

Defects in those oils that failed to pass muster included oxidation from excessive temperature, light or aging and addition of cheaper refined olive oils.  Other flaws may have been linked to improper processing or storage and use of damaged or overripe olives.

The complete report from the study, which is the first of its kind from an American college or university, is available online from the UC Davis Olive Center at: http://olivecenter.ucdavis.edu/.

The study was funded by Corto Olive, California Olive Ranch and the California Olive Oil Council.

Anecdotal reports of low-quality olive oils lurking behind extra-virgin labels have been floating about for some time but this is the first “empirical proof” to support those suspicions, according to Dan Flynn, executive director of the UC Davis Olive Center..

“The intent of the study was to provide consumers and retailers with an accurate picture of the quality of olive oils now being marketed through grocery stores and other retail outlets in California,” said Flynn, noting that the United States is the third-largest consumer of olive oil in the world.

“Our hope is that these findings will lead to improved methods for evaluating extra virgin olive oil, and increased consumer confidence that “extra virgin” on the label means extra virgin in the bottle,” he said.

Posted on Friday, July 16, 2010 at 6:30 AM

Strawberry fields forever

Methyl iodide – yes, that volatile chemical that could find use as a soil fumigant – has been in the news lately, and mostly in a negative light. In April, California’s Department of Pesticide Regulation made a preliminary decision to approve the use of methyl iodide as a fumigant under strict conditions, and soon after received more than 50,000 public comments.

Methyl iodide, it turns out, is not only toxic, like all fumigants, it “can cause cancer, brain damage and miscarriages.” Its potential use in California’s strawberry fields in place of its ozone-depleting and toxic cousin, methyl bromide, is what shot the compound into news orbit.

Why phase out methyl bromide as a soil fumigant? Answer: Ozone loss up in the stratosphere, leading to more ultraviolet light penetrating the Earth’s atmosphere, leading, in turn, to increases in skin cancer. When methyl bromide is released in the lower atmosphere, a fraction gets transported into the stratosphere where it undergoes a series of chemical reactions leading to stratospheric ozone depletion.

Cousin methyl iodide, on the other hand, is photolyzed quickly in the lower atmosphere, leaving none of it to escape into the stratosphere.

While public opinion currently leans heavily against the use of methyl iodide as a soil fumigant replacement, James Sims, a professor emeritus of plant pathology at UC Riverside, supports its use.  For one thing, it delivers results similar to methyl bromide, he says, and, second, it can be used safely. He explains that it is not applied directly to plants; it is injected into the soil two weeks before any plants are planted.

Methyl iodide is a liquid boiling at 42.5 degrees C or 108.5 degrees F. Sims says it is therefore safer for workers to handle than a gas like methyl bromide. Moreover, it can be applied using the same equipment with few or no modifications, and it is effective in reducing pest, weed and plant disease problems. Other alternatives — solarization, anaerobic soil disinfestations, crop rotation, steaming, etc. — are not effective, Sims says.

Critics are not convinced of methyl iodide’s relative safety and growers, meanwhile, continue to insist that their fields need a fumigant that poses no harm to our precious ozone layer.

How then might the controversy play out? We will have to wait and see – for several weeks at least. After processing the public comments received, state officials plan to weigh in on the “controversial effort to register the fumigant methyl iodide.”
Posted on Wednesday, July 14, 2010 at 6:29 AM

Oh no! Zucchini again!

I was only gone for 10 days, but when I came back the squash plants were just packed with zucchini — some that were as big as torpedoes (they got fed to the chickens) but many just the perfect size for harvest.  However, what do you do with 50 zucchini?  First stop, my neighbors. Got rid of 10 there.

Next, as 4th of July guests leave, they get a bag to take home; another 10 down . . . only 30 more squash to use or distribute.  What can you do?

Well, there are lots of ways to eat zucchini but I have found a couple of ways that are just yummy and healthy. 

The first recipe is easy.  

Zucchini and mozarella salad/appetizer

Slice the zucchini in lengthwise ¼ inch thick strips, drizzle with a little olive oil and grill on each side for a few minutes. Place the strips in a bowl with a little salt and pepper and a little more olive oil to cool. Then artfully place slices of fresh mozzarella cheese on plate along with the rolled up grilled zucchini strips, a handful of halved sun gold cherry tomatoes, fresh chopped basil, and a final little drizzle of olive oil. Makes a beautiful presentation and uses about 4 zucchini.

Only 26 left to use . . . .

Zucchini oven chips

This recipe, from Cooking Light, makes a great side dish with burgers or other grilled main course.

Slice the zucchini into rounds about ¼ inch thick. Dip into milk and then dredge in a mixture of seasoned breadcrumbs and parmesan cheese. Then place on an oven proof rack sprayed with cooking spray. Bake for 30 minutes in a preheated oven at 425 F until brown and crispy.

This uses about 5 smaller zucchini. Only 21 left . . .

The next recipe is the ubiquitous zucchini bread. There are dozens of recipes for that. Each recipe uses about 3 cups of shredded zucchini, which is about 3 small or 2 larger zucchini. Now only 18 left.

Zucchini pie is a lovely main dish. You can use pre-packaged pie dough or crescent rolls or make your own dough from scratch.

Line your pie pan with the dough.

In a large sauté pan, melt 2 tablespoons of butter. Sauté 4 cups of thinly sliced zucchini (about 4 small or 3 larger squash) and ½ cup chopped onions until tender. Add 3 tablespoons chopped fresh basil, 2 cloves of garlic, ¼ teaspoon of oregano and salt and pepper to taste.

In another large bowl, mix 2 eggs and 2 cups of shredded mozzarella cheese together. Add the zucchini mixture and gently stir. Pour mixture into pie crust. Bake at 375 F for 20 minutes or until a knife inserted into the filling comes out clean.

That takes us down to 14 more zucchini left. Sigh . . . I guess I should have only put in 6 plants instead of 12.

However, the good thing about zucchini is that you don’t have to use them all. The chickens will love you if you feed them squash (you have to open the fruit up for them though) and of course you can leave bags of zucchini at the doorsteps of your friends or on the desk of your office mates. They won’t hate you too much . . .

Posted on Monday, July 12, 2010 at 6:38 AM

It’s a scorcher! Beat the heat with healthy treats!


Summer time in the Central Valley means scorching temperatures in excess of 100 degrees, and sunshine that just won’t quit. When the thermometer heads north, we head to the freezer in search of a refreshing treat.  

Can you remember devouring an ice cream cone in all its melting glory? Gobbling it up in search of refreshment as the sun’s rays seem to pierce right through you? Savoring each bite as the excess fat and sugar runs down the arm to the elbow, before dripping onto the asphalt with a sizzle.

Wait a minute. What was that about excess fat and sugar?



Unfortunately, not all refreshing treats are created equal. Frozen summer time staples like ice cream, though OK in moderation, can increase the amount of fat and sugar you’re consuming with little nutritional benefit.
Lucky for us, connoisseurs of summer time refreshments have tips and recipes to help us stay cool, the healthy way.

If it’s frozen treats you’re after, try:

Frozen grapes
Full of antioxidants and portable, frozen grapes make a great treat without a sticky mess.




Frozen cherries


Packed with vitamin C, cherries are an excellent summertime snack. Simply de-stem and rinse the cherries. Pit the cherries and spread on a tray. Place in the freezer until frozen. Store them in an air-tight container in the freezer until you are ready to pop a few to cool off.


Fruit smoothies

Fruit Smoothies are a favorite!  Blend ½ c. vanilla low-fat soy or regular yogurt, ½ cup of your favorite fresh berries, 2 ice cubes and 2 tsp. vanilla extract until smooth.  Makes one cup.


Healthy ice cream
This recipe has tofu; it is healthy and safe for those who are lactose intolerant.  


Ingredients
12 ounces frozen strawberries or frozen peaches
14 ounces soft silk tofu
1 cup of sugar
2 ounces of a healthy oil
1 teaspoon lemon juice
1 teaspoon vanilla

Directions
1. Assemble ingredients and blend in a food processor or blender. 
2. Next, place the mixture in a plastic freezer zipper bag (one quart size) and seal. 
3. Place the healthy ice cream bag in a gallon size plastic bag filled with a couple of tablespoons of salt and plenty of ice and shake for five minutes.  You will cool off just shaking the bags!


Remember, when the temperature rises, choose wisely. Healthy alternatives to fatty, sugary, frozen treats are simple and delicious!

Wishing you a cool and healthy summer! For more healthy tips, click here.

Posted on Friday, July 9, 2010 at 6:29 AM

Growing peaches involves a relationship with the trees

San Joaquin Valley farmer Mas Masumoto famously described the joys of fruit eating in the opening pages of his book Epitaph for a Peach. The prologue reads like a love letter to the old Sun Crest variety, planted years ago by his Japanese-American father. Sun Crest peaches are juicy and delicious but lack some commercial attributes.

On eating a fruit he calls a “treasure,” Masumoto wrote:

“You lean over the sink to make sure you don’t drip on yourself. Then you sink your teeth into the flesh . . . This is a real bite, a primal act, a magical sensory celebration announcing that summer has arrived.”

Many Californians can share Masumoto’s experience of lovingly caring for a fruit tree, patiently waiting for the bounty to ripen and savoring fruit still warm from the sun. However, UC Cooperative Extension farm advisor emeritus Garth E. Veerkamp suggests gardeners not enter a relationship with an orchard before taking time for thoughtful consideration.

“When the decision to create a home orchard is based on little more than desire to plant a few trees and anticipate fruit, then failure is the probable outcome,” Veerkamp said. “When a home orchard is based on an understanding that it is, in fact, a living expression of genetics interacting with soils, weather, tree spacing, pests, and many other factors, then the outcome should be one of success."

Veerkamp wrote questions to guide aspiring orchardists in an inward examination of their lives before planting trees. Ask yourself:

  • Do I really have the desire, time and stamina to establish and maintain the orchard?
  • To what extent will the demands affect my relationships with others around me?
  • Do I understand the cultural demands the orchard places on me and the yields to expect under good management?
  • Can I accommodate, or, if not, balance the demands of tree care and harvest with my desire to not be tied down or to travel?

To help Californians understand orchard demands, the University of California has developed The California Backyard Orchard, a website with detailed information on orchard site considerations, tree selection, propagation, preparation, planting, irrigation, pollination, pruning, training, fertilization, fruit thinning pests and diseases.

With the help of the website, the full scope of orchard responsibilities can be balanced with the alluring promise of abundant and delicious fresh fruit before the shovel digs into the dirt.

Peach trees need loving care.
Peach trees need loving care.

Posted on Wednesday, July 7, 2010 at 6:20 AM

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