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UC Food Safety

UC Food Blog

Treat your mandarins right

Mandarins may look like little oranges, but scientists believe that their distinct attributes demand special treatment to maintain a fresh, juicy and tangy character.

“We think the flavor of mandarins declines much more rapidly than oranges,” said Sue Collin (right), a UC Riverside staff research associate who is based at the UC Kearney Agricultural Research and Extension Center in Parlier.

The way oranges are set out at the grocery store or on home counter tops could be trouble for the more delicate mandarin. And when mandarins make a six-week sea voyage to the Pacific Rim, will Asian consumers find the fruit acceptable?

In order to provide farmers, shippers and retailers accurate information about the impact of different storage temperatures on the quality of the fruit, Collin is working with UC Riverside sub-tropical horticulturalist Mary Lu Arpaia and USDA plant physiologist Dave Obenland to understand the changes in mandarins stored at a variety of temperatures, at different humidity levels, for various periods of time.

“A grocery store may be holding fruit at room temperature, 68 degrees or even warmer,” Collin said. “We’re comparing fruit that has been stored in very controlled atmospheres – at temperatures in the 40s, 50s and 60s.”

When it comes to understanding the acceptability of fresh fruit, nothing can match the human palette.

Collin recruits staff based at Kearney to take a break from their jobs to come to a laboratory built at the agricultural research station specifically for sensory testing. The 1,100-square-foot laboratory features neutral white paint and broad-spectrum lighting. The ventilation system was designed to minimize distracting odors. Inside, six tasting booths each have small windows that open to the kitchen area, where samples are prepared.

“We do quite a bit of testing to see if our volunteers can tell the difference in fruit stored at different temperatures,” Collin said.

In conjunction with the human testing, Obenland studies the fruit’s chemical composition to find out if objective numerical values correlate with the more subjective findings of the human tasters.

Although the optimal storage temperature for mandarins is still under investigation, Collin suggested consumers should keep their mandarins in the refrigerator at home for best results.

“I think the flavor holds better and the fruit lasts longer in the refrigerator,” Collin said.

This research is being funded in part by the Citrus Research Board.

Posted on Tuesday, February 22, 2011 at 10:07 AM

Vegetables, farmers, kids & adventures

Unusual vegetables and fruits get me every time. Rainbow carrots? Watermelon radishes? Party cauliflower? Romanesco?

Bright colors, quirky shapes and even creative names can stop me in my tracks at any farmers market. If I can't identify it, I feel compelled to buy some to take home and share.

The small-scale farmers who are likely to be selling these tempting curiosities are counting on customers like me (and maybe you too?). They often cannot compete on low prices alone, but small-scale farmers can succeed by differentiating their products from more widely available commodities through taste, appearance, harvest time or other qualities. Planting a new specialty crop can help a small-scale framers carve out a profitable niche in the marketplace.

For that reason, identifying and field-testing specialty crops is a focus of the UC Small Farm Program — and of a new project officially launched this week.

The UC Small Farm Program is a partner in the "Great Veggie Adventure," an effort launched by the makers of Hidden Valley Salad Dressings to identify a vegetable that few people have heard of, but that children might just love. The Small Farm Program is helping identify vegetable candidates that meet criteria highlighted by a survey of elementary school students' vegetable preferences.

Our farm advisors will be growing varieties of rainbow carrots, watermelon radish, party cauliflower and Romanesco in demonstration plots around the state. Though small farm advisors frequently test and demonstrate interesting new crops, this time they will be bringing kids behind the scenes, with blog posts and video updates from their fields.

Will these "new" vegetables snag the curious tastebuds of kids? We'll have to wait and see.

But I know some vegetables that I'll be keeping an eye out for at my farmers market...

Did you know?

  • Aziz Baameur, UC Cooperative Extension farm advisor (also with the Small Farm Program) and Maria Giovanni, nutrition advisor, conducted field tests and tasting panels with a rainbow's array of carrots. Read more about it in UC Delivers.
  • The Great Veggie Adventure is part of the "Love Your Veggies" program, now in its fifth consecutive year. Hidden Valley created the Love Your Veggies program in 2007 after a study by UC Cooperative Extension Butte County and the Expanded Food and Nutrition Education Program. Read about their study in this ANR News Blog post.

Video: Manuel Jimenez, UC Cooperative Extension farm advisor in Tulare County, introduces his work with the UC Small Farm Program — and the program's involvement in the "Great Veggies Adventure"

Posted on Thursday, February 17, 2011 at 3:54 AM

Sharing the 'California dream'

We live in an orchard. It’s pretty much like the California dream that Sunkist and the railroads promised to people back East and to dust bowl refugees many years ago – an orange tree in your own backyard! For many of us in the Sacramento region, the dream came true.

Right now the citrus is ripe. Once you start looking, you see it everywhere – bright navel oranges, juicy grapefruit hanging in clusters, glistening lemons and sweet tangerines – some behind fences and some right out front by the street.

Often the trees are big and old, planted long ago. Much of this urban and suburban fruit doesn’t get harvested; people are too busy, the trees get too tall, or there’s just too much fruit to handle at one time. Meanwhile thousands of people in our own community don’t have fruit, fruit trees, backyards or even homes.

Soil Born Farms Urban Agriculture Project is helping Sacramento people share the California dream with their neighbors through the Harvest Sacramento project. Last Saturday I joined a crew of volunteers to pick citrus in Sacramento’s Oak Park neighborhood for donation to the Sacramento Food Bank. I had a great time doing it and met some wonderful folks. The food bank distributes the fruit at mobile food pantries over the next week.

My friend and I arrived at McClatchy Park at 9 a.m. along with a couple of dozen other volunteers. We divided into four or five teams, loaded our vans and pickups with ladders, buckets, picking poles and boxes provided by Soil Born and headed off to the first of three houses whose residents had agreed to let us pick their fruit. Our team included a mom with two enthusiastic children, three young members of Sacramento’s new Green Corps in matching tee shirts, the two of us, and Shannon, our team leader.

Shannon made contact with the resident at the first house, gave us safety instructions, and we got started. We set up ladders and picked by hand and with extendable picking poles with little baskets on the end to grab the fruit. This house had a small orange tree and a large lemon tree in the side yard. We quickly picked a box of oranges, stripping the tree and delivering a few to the front door for the owner to enjoy, then spent about a half hour picking three boxes of lemons from the upper half of the lemon tree, leaving the lower fruit for the homeowners to pick. Then we were off to the next house on our list.

The second house had an awesome huge orange tree and a smaller lemon tree in the backyard, which kept us all busy and yielded another four boxes of fruit. Just a few houses down the street, at our last stop, was the biggest grapefruit tree I had ever seen. We extended the picking poles all the way, set up all our ladders, picked four boxes of grapefruit and left what we couldn’t reach. We took all the fruit back to the park, filling big bins that the food bank picked up, and said goodbye to our new friends. Of course we got to take a few tasty samples of the fruit home with us to enjoy.

Soil Born Farms’ Harvest Sacramento Project will be harvesting fruit in the South Land Park neighborhood on Feb. 19 and in the Curtis Park neighborhood on Feb. 26. Volunteers and donations of fruit that needs harvesting are both welcome. For more information:

Posted on Tuesday, February 15, 2011 at 8:01 AM

EFNEP helps us eat well on the cheap

Last week (Jan. 31, 2011) the U.S. Department of Agriculture released its revised 2010 Dietary Guidelines for Americans. They are “the federal government's evidence-based nutritional guidance to promote health, reduce the risk of chronic diseases, and reduce the prevalence of overweight and obesity through improved nutrition and physical activity,” according to the press release.

I scanned the press release for news that cookies have been designated an essential food group. No luck. I confess, I didn’t read the entire 95-page pdf, but surely any such rocking revelations would have been reported in the press release.

Because more than one-third of children and more than two-thirds of adults in the United States are overweight or obese, the guidelines emphasize eating less and moving more.

I wasn’t surprised to see among its 23 key recommendations the advice to drink more water instead of sugary drinks, eat a variety of healthy foods and reduce salt. I expected the recommendation to eat more fruits and vegetables, but now it’s more explicit.

They say half of my plate should be covered in fruits and veggies. And mix it up – eat a variety of vegetables and protein sources. (I used to eat broccoli beef almost every day for lunch, until the day I found an insect in it.)

Many people think they have to spend more for nutritious meals, that fresh produce and meat are expensive. However, UC’s Expanded Food and Nutrition Education Program, or EFNEP, gives tips on how to make healthful food choices when you’re on a limited income. (Unless your name is Mark Zuckerberg, whose income isn’t limited?)

Chapter 6 of the Dietary Guidelines acknowledges that our environment – composed of school, workplace, social groups, culture and so on – influences our food and exercise choices. However, our communities don’t excuse our behavior because ultimately we make our own choices, it essentially says. We may have more access to healthy foods and opportunities to engage in physical activity than we realize. Connie Schneider, EFNEP Council chair, sees EFNEP as a vehicle to help families navigate their complicated food environments.

“Our educators facilitate group discussions to resolve food issues from shopping on a budget to getting their children to eat healthier foods,” said Schneider, who is also a UC Cooperative Extension nutrition advisor.

The EFNEP staff meets with families and children in a variety of community settings, including schools, shelters and transitional housing. Nutrition educators teach them how they can stretch their food dollars and still enjoy a healthy diet. They share recipes for nutritious meals that are simple to prepare as well as inexpensive. I love to eat, but have little patience for cooking. Watching a nutrition educator demonstrate how to make chili, I found myself thinking, “That’s so quick and easy, even I would do that.”

Sometimes a new way of preparing a familiar vegetable encourages me to eat more veggies.

The EFNEP website spotlights a Fresh Pick of the Month, such as cauliflower. The site gives the nutritional benefits of cauliflower, serving tips and recommendations for handling and storing the vegetable. It also provides a recipe for cauliflower soup.

The nutrition educators also publish monthly newsletters, in English and Spanish, featuring a recipe and healthful suggestions, such as walking to the restaurant and sharing entrees when you go out to eat. Although the nutrition program is designed to assist families and children whose resources are limited, we can all use the suggestions to improve our health and save some money.

Posted on Thursday, February 10, 2011 at 8:09 AM

Increase your food security, plant a fruit tree now!

I was struck the other day, when hearing about the world-wide soaring cost of foods, that we are incredibly lucky to live in California where food is so readily available to us. I was listening to this news on the radio as I was returning from my weekly trek to the grocery store and farmers market loaded with wonderful local whole fruits and vegetables of really high quality. I felt so fortunate and thankful at that moment that I could buy everything I wanted or pick what I wanted from my winter garden or my fruit laden citrus trees. 

You can increase your own food security by planting food in your own garden . . . and you can start by planting a fruit tree now. February is the time that you can plant what are known as “bare-root” fruit trees, grapevines and berries. Fruit trees are now widely available at local nurseries or through mail order websites and catalogs.

Pick a tree fruit variety that you really love and something that you can’t purchase easily from the market. For me, this would be some of the more fragile freestone peaches such as Rio Oso Gem, or JH Hale. Or, you might pick a space saving self-pollenating variety of cherry such as Stella.

I always think great apricots are difficult to purchase in the markets so planting an apricot makes sense . . . they are relatively pest free, mostly self-fruitful and make beautiful landscape trees. My favorite apricot varieties include Patterson, Tilton and Harcot. 

Just a note though, not all fruit varieties will grow in all climate zones. If you live in the San Joaquin or Sacramento valleys, then you are in luck because these are the primary stone fruit growing zones of California. If you live in the inland valleys of the coastal range, or in the foothill regions of the Sierras, you can grow most fruit varieties as well. If you are, however, on the coast or in Southern California, you may want to pick varieties that are "low chill."  For information on the best varieties for your climate zone go UC's California Backyard Orchard website.

If space is an issue, consider growing genetic dwarf fruit trees in containers or purchase semi-dwarf or standard varieties that can be kept small using the "fruit bush" method of training. By using the fruit bush system, you have more varieties of fruit to choose from. The fruit bush is a growing system that is perfect for backyards. You basically do most of your pruning in the summer. You keep the tree small by shearing it back two times during the growing season. You never allow it to grow any taller than your head height. 

By keeping the fruit tree short, it is easier to harvest, deal with pest issues and cover with nets if you have a squirrel problem. For more information on how to prune a fruit bush or other fruit tree training systems, the UC Cooperative Extension Office in Sacramento County has an excellent horticulture note.

If you are unsure of how to choose, plant or care for your fruit trees, grapevines or berry bushes, there is a UC Master Gardener nearby who can answer your questions. Click here to find your local Master Gardener program.

Posted on Tuesday, February 8, 2011 at 8:05 AM

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