Acrylamide

[Guest guest]

This came up awhile ago, and I recently ran across it again. There is a LOT

more info about it now, on the web. It definitely points out the

wisdom of NT.

First, it is formed when baked goods are baked at over 120 degrees C. Jibes with

what

Sally wrote 20 years ago ... boil your food, or bake it slowly.

http://www.sdwg.com/index.cfm?show=4 & id=13744

The contaminant, acrylamide, is formed when certain foods, particularly

plant-based foods rich in carbohydrates and low in protein, are cooked at

temperatures higher than 120 decrees Celsius, and the UN agencies have called

for preparation technologies that significantly lower the acrylamide level.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=pubmed & dopt=Abstra\

ct & list_uids=15168561

Some model studies were performed using various agricultural Products, to

clarify the relation between cooking conditions and production of acrylamide

(AA). Disc chips made from dried mashed potato, corn meal, wheat flour, rice

flour (jyohshin-ko) and glutinous rice flour (shiratama-ko), and dried sesame

(arai-goma) and dried almond were baked at 120-200 degrees C for 5-20 min, and

the samples were analyzed for the levels of AA. When the samples were baked for

10 min, the highest production of AA was observed at 180-200 degrees C. When the

samples were baked at 180 degrees C, AA levels in agricultural products except

sesame were highest after baking for 10 min. Vegetables and fruit were baked at

220 degrees C for 5 min with a oven, high AA concentrations were found in baked

potato, asparagus, pumpkin, eggplant and green gram sprouts. Concentrations of

AA in potato, asparagus and green gram sprouts baked after being pre-cooked by

microwave irradiation were higher than those in the products baked without being

precooked. On the other hand, the precooking by boiling reduced the production

of AA by baking to 1/10-1/4. Acrylamide was not found in microwaved or boiled

vegetables. High free asparagine concentrations in crops tended to result in

high concentrations of AA being produced by heating the agricultural products.

120 degrees C is only 248 F. 180C is 356 F. 200C is 392 F. So we aren't talking

REALLY high heats here (though fast

food fries are MUCH hotter and have really high levels of Ac.)

In baked goods, the content varies a LOT. It seems to be highest

in whole wheat products, and lower in oat products. Meusli is

about the best cereal (tradional meusli isn't even baked at all).

http://cspinet.org/new/pdf/acrylamide_product_charts.pdf

Fermenting reduces the acrylamide content:

http://www.aaccnet.org/cerealchemistry/abstracts/2004/0805-03R.asp

Free asparagine is an important precursor for acrylamide in cereal products. The

content of free asparagine was determined in 11 milling fractions from wheat and

rye. Whole grain wheat flour contained 0.5 g/kg and whole grain rye flour 1.1

g/kg. The lowest content was found in sifted wheat flour (0.2 g/kg). Wheat germ

had the highest content (4.9 g/kg). Fermentation (baker’s yeast or baker’s yeast

and sourdough) of doughs made with the different milling fractions was performed

to investigate whether the content of free asparagine was reduced by this

process. In general, most of the asparagine was utilized after 2 hr of

fermentation with yeast. Sourdough fermentation, on the other hand, did not

reduce the content of free asparagine as efficiently but had a strong negative

impact on asparagine utilization by yeast.

Note that the wheat GERM has the most ... I wonder if the rice bran has the

same kind of issues, might be another reason the Asians went to

so much work to polish theirs.

If you are curious about your favorite foods, here is a list. Note that MOST

foods didn't have

detectable amounts of Acr. Fried potatoes and low water content

baked goods are the prime offenders. (Arrowroot cookies were high, apple

pie low, graham crackers awful). And black olives are bad, for some reason.

http://www.cfsan.fda.gov/~dms/acrydat2.html

-- Heidi Jean