Food & Nutrition Research Briefs, October 2006
Walnuts provide fiber as well as minerals and
other nutrients. Image courtesy Walnut Marketing Board
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Already shown in some studies to reduce
"bad" (LDL) cholesterol, walnuts may have yet another way of
enhancing your cardiovascular health.
Tests on 100 laboratory hamsters that ate
feed containing ground walnuts for a half-year showed they had significantly
lower levels of a protein called endothelin in their arteries. This protein
helps regulate blood pressure. But, it also causes inflammation of arteries and
growth of sticky deposits, called plaque, in blood vessels. These two
conditions contribute to heart disease, the leading cause of death in the
United States.
Walnuts suppressed heart artery endothelin
when fed at amounts equal to an adult human's eating from three to eight
handfuls of walnuts daily (Journal of Nutrition, volume 135, pages 428
to 432). The study was an international collaboration between scientists with
ARS, the University of California-Davis and University of Padova (Italy).
Whether this beneficial effect occurs in
people at more moderate amounts of walnuts needs further study.
The California Walnut Commission, Sacramento,
Calif., helped fund the research.
For details, contact:
Wallace
H. Yokoyama, (510) 559-5695; USDA-ARS
Western
Regional Research Center, Albany, Calif.
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New research findings suggest adding blueberries
and strawberries to the diet may help slow the decline that often occurs with
aging.
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Blueberries and strawberries may help slow
the decline in learning and memory that often occurs as we age. That's
according to new findings from tests with 60 laboratory rats, studied for about
three months.
Rats in either of three groups of 20 each ate
either a standard feed or feed with blueberry extract equal to that of a daily
one-cup portion for humans, or feed with strawberry extract equal to a daily
one-pint bowlful.
After two months on the regimens, half of the
rats in each group were treated to induce aging. Compared to the aged rats on
nonsupplemented feed, the aged-but-supplemented rats performed better in a test
of their ability to find, and in some cases remember, a particular feature in
their environment.
The new findings add to a series of research
studies published during the past eight years showing reduced or reversed
declines in brain function among rats whose feed was supplemented with either
blueberry, cranberry or strawberry extracts or Concord grape juice.
ARS-funded scientists at the Jean Mayer USDA
Human Nutrition Research Center on Aging, Tufts University, Boston, Mass.,
conducted the research in collaboration with investigators at the University of
Maryland-Baltimore County and published their findings in Neurobiology of
Aging (online July 13, 2006).
For details, contact:
Barbara
Shukitt-Hale, (617) 556-3118; ARS Jean Mayer USDA
Human
Nutrition Research Center on Aging, Boston, Mass.
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A plant chemical isolated from fresh blackberries
may inhibit tumor growth.
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Fresh blackberries contain a compound that
may interfere with genes associated with cancer-promoting agents. The purified
compound, cyanidin-3-glucoside (C3G), inhibited growth and spread of skin and
lung tumors in tests with laboratory mice (Journal of Biological
Chemistry, volume 281, pages 17359 to 17368).
The number and size of skin tumors were
significantly reduced among mice that had been supplemented with C3G, when
compared to those that had not, the scientists found. In another study, the
growth of lung tumors and spread of the cancer to other organs were
significantly reduced in immune-system-suppressed mice fed the C3G
compound.
Scientists with ARS at Beltsville, Md., and
the National Institute for Occupational Safety and Health, Morgantown, W.Va.,
collaborated in the research.
For details, contact:
Shiow
Y. Wang, (301) 504-5776, ext. 427; USDA-ARS
Henry
A. Wallace Beltsville Agricultural Research Center, Beltsville, Md.
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An ARS-developed technique enhances extraction of
lycopene from an excellent source--watermelon!
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Watermelon, besides being fun to eat, is an
excellent source of lycopene--a red-pigmented antioxidant thought to guard
against heart disease and some cancers.
Now, an ARS researcher based in Lane, Okla.,
has developed a new technique that makes it easier to extract lycopene from
watermelon flesh and juice.
Users can avoid damaging the fragile
membranes of the tiny structuresorganellesthat protect the
lycopene. This gentle approach yields lycopene that is more stable and thus has
a longer shelf life.
Lycopene can be processed into a powder,
paste or liquid suitable for use as a nutrition supplement or food coloring.
ARS is seeking a patent for the method, which
might also be used to extract lycopene from tomatoes, guava, rose hips and pink
grapefruit.
For details, contact: Wayne W.
Fish, (580) 889-7395, ext. 261; USDA-ARS
South
Central Agricultural Research Laboratory, Lane, Okla.
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Ripening fruit of Deglet Noor date palm.
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Sweet, chewy dates provide healthful
antioxidantsmostly the kind known as phenolics. But the levels of these
compounds vary according to what variety of date you're eating, ARS and
University of California-Davis scientists have found.
Deglet Noor dates, the leading commercial
variety in the United States, logged a higher antioxidant score than five other
types of dates grown in California, the nation's leading producer of this
exotic crop.
Other ARS-led research yielded new insights
into the genetic diversity of date trees safeguarded in a unique collection
that ARS curatesthe Riverside, Calif.-based National Clonal Germplasm
Repository for Citrus and Dates.
For details, contact:
Robert
R. Krueger, (951) 827-4399; USDA-ARS
National
Clonal Germplasm Repository for Citrus & Dates, Riverside, Calif.
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Food technologist Yaguang Luo and plant
pathologist James L. McEvoy assemble a sample of fresh-cut cilantro.
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You can't hear the fruits and veggies in your
refrigerator breathe, but they do. They take in oxygen and give off carbon
dioxide. Pairing your fresh produce with a wrapping, or film, best suited to
the fruit or veggie's respiratory needs enhances the length of time it will
stay fresh and appealing, new tests confirm.
The wraps, newer versions of the familiar,
clear-plastic films already used widely in home and commercial kitchens, act as
modified-atmosphere packaging that regulates the flow of oxygen and carbon
dioxide to and from packages of produce.
While the concept isn't new, ongoing
experiments by ARS scientists at Beltsville, Md., provide some of the most
up-to-date findings about the unique packaging needs of some half-dozen
different fruits and veggies, including baby spinach, carrots, cilantro,
iceberg and romaine lettuces and salad savoya cabbage relative
(Journal of Postharvest Biology and Technology, volume 33, pages 51 to
59).
Experiments with fresh cilantro leaves, for
example, showed that one such film can keep this tomato-salsa seasoning fresh
for up to 14 daysinformation useful to produce packers and shippers, as
well as film manufacturers.
For details, contact:
Yaguang
Luo, (301) 504-6186; USDA-ARS
Henry
A. Wallace Beltsville Agricultural Research Center, Beltsville,
Md.
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Food technologist Eunhee Park instructs taste
tester Amy B. Blodgett on scientifically evaluating Fuji apple qualities.
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Experimental washes, also called antibrowning
dips, for freshly sliced apples show promise for keeping the fruit safe to eat,
while at the same time protecting its appealing textures, flavors and colors
(Food Microbiology, volume 21, pages 319 to 326). Laboratory experiments
by ARS researchers based in Beltsville, Md., showed these protective effects in
tests with freshly cut apple slices.
Today's calcium-ascorbate-based washes
forestall browning but apparently don't knock out as extensive a range of
unwanted microbes, according to the Maryland scientists. The newer
formulations, not only kept the apple slices from browning, but also killed
unwanted microbes.
For details, contact:
Arvind
A Bhagwat, (301) 504-5106; USDA-ARS
Henry
A. Wallace Beltsville Agricultural Research Center, Beltsville,
Md.
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Now on the web: updated nutrient profiles of
mushrooms such as white button.
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Besides adding their distinctive flavors and
textures to salads, soups, burgersand moremushrooms also give us
key nutrients like copper, potassium, folate and niacin. New nutrient data for
seven different kinds of mushroomscrimini, enoki, maitake, oyster,
portabella, shiitake and white buttonare now available on the World Wide
Web at: www.ars.usda.gov/nutrientdata as part of the
USDA National Nutrient Database for Standard Reference, Release 19.
ARS scientists at the Beltsville (Md.) Human
Nutrition Research Center led the mushroom-data-gathering project, which was
funded in part by the Mushroom Council, Dublin, Calif.
For details, contact:
David
B. Haytowitz, (301) 504-0714; USDA-ARS
Beltsville
Human Nutrition Research Center, Beltsville, Md.
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Perfect for a cold day: Italian potato soup. Make
it with russeted potatoes such as ARS' new Blazer Russet. Photo courtesy
United States Potato Board.
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Whether sold fresh or processed into frozen
potato products, Blazer Russet potato is a top-quality tuber. The oblong,
medium-to-large veggie weighs in at about seven to eight ounces and has the
characteristic light netting, or russeting, on its brown-to-tan skin, with
firm, cream-white or white flesh inside.
ARS scientists at Aberdeen, Idaho, and their
University of Idaho, Washington State University and Oregon State University
colleagues put the tuber through nearly two decades of rigorous laboratory,
field and test-kitchen scrutiny before deciding in December 2005 to make this
experimental potato a named variety.
Blazer Russet is ready to harvest at about
the same time as the popular, early-maturing Shepody potato. But Blazer
provides higher yields of premium, U.S. No. 1 potatoes.
For details, contact:
Richard
G. Novy, (208) 397-4181, ext. 111; USDA-ARS
Small
Grains and Potato Germplasm Research Unit, Aberdeen, Idaho.
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Jeanne gooseberriesnew from ARS plant
breeders in the Pacific Northwest. Image courtesy National Clonal Germplasm
Repository.
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Summertime treats of tomorrow might include a
chilled slice of gooseberry pie, made with a luscious new, dark-red gooseberry
called "Jeanne." Scientists with the ARS National Clonal Germplasm
Repository, Corvallis, Ore., made the berry available to other researchers and
to plant nurseries for the first time this year, following more than 12 years
of lab, greenhouse and outdoor tests.
Jeanne gooseberry plants each produce about 3
pounds of sweet, good-sized fruit every yearan impressive harvest that
should please commercial growers and backyard gardeners alike.
Jeanne is named for Cheryl Jeanne Gunning,
who worked at the Oregon laboratory and is now deceased.
In contrast to most other gooseberries, this
plump newcomer is resistant to white pine blister rust, a disease that's a
cosmetic problem to gooseberry leaves but can be devastating to pines. The
gooseberry also fends off the microbe that causes powdery mildew, the berry's
worst disease enemy. What's more, the plant doesn't succumb to attacks by
aphids and sawflies.
For details, contact:
Kim E.
Hummer, (541) 738-4201; USDA-ARS
National
Clonal Germplasm Repository, Corvallis, Ore.
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