www.checkbiotech.org ; www.raupp.info ; www.czu.cz

Scientists at the University of Idaho have produced a genetically modified
potato variety of Ranger Russet with enhanced French fry aroma, and reduced
amounts of processing-induced acrylamide, December 2006 by Stephen
Daniells.

And since the genetic modification was accomplished without inserting any
foreign genetic material into the potato's genome, the researchers hope to
calm any consumer concerns about the new spud variety.

Acrylamide is a carcinogen that is created when starchy foods are baked,
roasted, fried or toasted. It first hit the headlines in 2002, when
scientists at the Swedish Food Administration first reported unexpectedly
high levels of acrylamide, found to cause cancer in laboratory rats, in
carbohydrate-rich foods.

Since the Swedish discovery a global effort has been underway to amass data
about this chemical. More than 200 research projects have been initiated
around the world, and their findings co-ordinated by national governments,
the EU and the United Nations.

Writing in the Journal of Agricultural and Food Chemistry, the Idaho-based
researchers report that by reducing the expression simultaneously of the
Ranger Russet's tuber-expressed polyphenol oxidase (Ppo), starch-associated
R1, and phosphorylase-L (PhL) genes, achieved without introducing any
foreign DNA.

"By committing to all-native DNA transformation methods for the
incorporation of output rather than input traits, we hope to address at
least some consumer concerns about the genetic modification of food crops,"
wrote lead author Caius Rommens in the Journal of Agricultural and Food
Chemistry.

The researchers report that, by reducing the expression of these specific
genes, when the potatoes were processed and fried to produce French fries,
the fries contained about one-third the acrylamide content of control fries.

"Because consumption of French fries was recently estimated to contribute to
about 16 per cent of the total dietary intake of acrylamide [in the US]
(0.07 micrograms per kg of body weight/day), application of the "low
acrylamide" fries would reduce the daily acrylamide intake by more than 10
per cent," they said.

Sensory evaluations, by a panel of eight professionally trained experts,
also showed that, somewhat unexpectedly, the sensory attributes were
enhanced in the 'intragenic' spuds.

"Our results demonstrate that a multigene silencing construct enhanced the
performance of Ranger Russet in seven different ways: black spot bruise
resistance, reduced cold-induced sweetening, reduced stress-induced sugar
ends, enhanced fry aroma, reduced amounts of processing-induced acrylamide,
reduced starch phosphate content, and increased starch," wrote the
researchers.

"We have shown that both the sensory and nutritional characteristics of
potato can be improved by simultaneously silencing the tuber-expressed Ppo,
R1, and PhL genes," they said.

The news could see the Ranger Russet expand its current market penetration
in French fry production, from its current level of about 20 per cent. The
limited use has been put down to storage problems, including sensitivity to
bruising and cold-induced sweetening.

Compared to more commonly used Russet Burbank, the Ranger Russet has
superior yields and greater disease resistance.

"By replacing some of the acreage that is currently occupied by Russet
Burbank, it will also be possible to increase yields and lower costs for
disease control," said Rommens.

The news could also see Ranger Russet growing increased in Europe. The
variety is said to have excellent adaptability.

[www.nutraingredients.com]

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