I'm not sure how I feel about this news report which follows. A new,
edible film has been developed which in the near future may be applied
to meats, fruit and vegetables. The product will release anti-
microbials when nasty pathogens are present. While in one hand it
appears to be a potential solution for the food poisonings we hear so
much about in the press, I am also concerned that consuming anti-
microbial compounds may not be a good idea. Read the press release
which follows, and my editorial comments at the end.

>From Newswise wire services:

Ready-to-eat meats are popular with consumers. But after the initial
food processing, they are also vulnerable to recontamination by
pathogenic bacteria. A solution turns out to be an application of an
antimicrobial-incorporated edible film coating that will fend off the
pathogens.

"We have used film coatings with raw and cooked ready-to-eat meat
products," said Navam Hettiarachchy, a food science professor in the
University of Arkansas System's Division of Agriculture who led the
research for the Food Safety Consortium. "We have also included red
meat in our studies as well. In all these products, we have observed a
protective effect of antimicrobial incorporated edible films against
the pathogens."

The researchers used a whey protein film coating as a vehicle for the
antimicrobials. The actual barrier to pathogens was provided by
various combinations of grape seed extract, nisin (a peptide, protein
fragment), malic acid and EDTA, which is a ring-forming compound of
metal ion known as a chelator.

The tests showed effective results in controlling the growth and
recontamination of Listeria monocytogenes, Salmonella Typhimurium and
E. coli O157:H7 on ready-to-eat meat products. Hettiarachchy's team
tried different combinations of the antimicrobials and found some
variances in levels of effectiveness. For example, in experiments on
turkey frankfurters, a combination of nisin, malic acid and EDTA was
more effective against E. coli O157:H7 when grape seed extract was not
part of the mix than when it was included.

"In most of the cases we focused on the type of meat products,"
Hettiarachchy said. "The types of proteins, lipids and other
components will vary in each meat product. The protective effect is
based on the type of antimicrobials and the product matrix, and the
film acts as a vehicle to deliver antimicrobials." She said the film
containing antimicrobials was effective for reducing pathogens on raw
chicken, ready-to-eat chicken and red meat, and the degree of
effectiveness was dependent on the product.

The key to the workings of edible film on meat is the ability to
sustain the release of antimicrobials against the pathogens. The
antimicrobials are held in the film matrix by weak forces, not by
chemical bonding.

"The antimicrobials can be released immediately or the release can be
delayed from the film matrix based upon the affinity of antimicrobials
to various amino acids and others that are present in the film,"
Hettiarachchy said. "A greater affinity of antimicrobials to the film
matrix will facilitate sustained release of antimicrobials and will
extend the shelf life of the product."

Some industrial interest is already being shown in the edible film.
Hettiarachchy said there are prospects of its commercialization and
some companies are looking into its use for coating fruits, vegetables
and even flowers. [END]

My editorial comments: While I would love to see some progress in the
war against food contamination, I would resist any effort to have a
broad-based antimicrobial compound applied to my food. The contents of
that compound don't appear to be a natural part of our environment and
it wouldn't fit my lifestyle as a result. However, there is an
additional concern here . . . that is, too many products now have an
"anti-microbial" element to them, and the result has been huge armies
of antibiotic-resistant organisms that we now have to deal with.
Microbes learn fast, and they adapt to their environment at light
speed. If we allow anti-microbial films on our foods, we would in
effect be producing future strains of microbes that would be
potentially quite nasty. This idea of a film applied to our food is
really a bandaid; instead of developing better quality processes to
prevent contamination, companies seek to find a way to simply "spray
and go" to avoid the bugs.

Lastly, our bodies have many good types of bacteria at work in various
functions. These probiotic bacteria could vanish if the food we ate
contained anti-microbial films of the sort described above.

Dave

Full text article above extracted from http://shamvswham.blogspot.com/

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