Door uitputting van
landbouwgronden meer acrylamide in graan.*
Onderzoek van de universiteit
van Reading en Rothamsted Research in Engeland heeft aangetoond dat graan,
gekweekt op gronden die nog maar weinig sulfaten bevatten wel
30x meer asparagine bevat dan graan gekweekt op niet uitgeputte grond.
Uitgeputte grond ontstaat hoofdzakelijk doordat zoveel en zovaak mogelijk wil
oogsten. 30x meer asparagine betekent dat als van het graan door verhitting bloem
gemaakt wordt de hoeveelheid kankerverwekkend acrylamide wel 6x keer hoger is.
Voor het eerst in 2002 werd bekend dat acrylamide ontstond bij verwarming van
bepaalde koolhydraten en aminozuren zoals asparagine. Daarom word acrylamide
gevonden in voedsel zoals frites, chips, brood
enz.
Dit is het eerste onderzoek
dat aantoont dat verarming van landbouwgronden zorgt voor meer ongewenste nutriënten
in ons voedsel.
Formation
of High Levels of Acrylamide during the Processing of Flour Derived from
Sulfate-Deprived Wheat
Nira
Muttucumaru, Nigel G. Halford, J. Stephen Elmore, Andrew T. Dodson, Martin Parry,
Peter R. Shewry, and Donald S. Mottram*
Crop
Performance and Improvement Division, Rothamsted Research, Harpenden,
Hertfordshire AL5 2JQ, United Kingdom, and Department of Food Biosciences,
University of Reading, Whiteknights, Reading RG6 6AP, United Kingdom
The
study was financially supported by the Biotechnology and Biological Sciences
Research Council in conjunction with the Food Standards Agency (grants
BB/C508634/1 and BB/C508669/1).
Abstract:
When wheat was grown under conditions of severe sulfate depletion, dramatic increases in the concentration of free asparagine were found in the grain of up to 30 times as compared to samples receiving the normal levels of sulfate fertilizer. The effect was observed both in plants grown in pots, where the levels of nutrients were carefully controlled, and in plants grown in field trials on soil with poor levels of natural nutrients where sulfate fertilizer was applied at levels from 0 to 40 kg sulfur/Ha. Many of the other free amino acids were present at higher levels in the sulfate-deprived wheat, but the levels of free glutamine showed increases similar to those observed for asparagine. In baked cereal products, asparagine is the precursor of the suspect carcinogen acrylamide, and when flours from the sulfate-deprived wheat were heated at 160 C for 20 min, levels of acrylamide between 2600 and 5200 mcg/kg were found as compared to 600-900 mcg/kg in wheat grown with normal levels of sulfate fertilization. (Nov. 2006) (Opm. Meer over acrylamide en hoe te vermijden)