decontamination of BSC with formaldehyde

[ecoli at cix.compulink.co.uk]

Hello there,
Any fermented milk experts out there ?

Curious phenomenon. Friend makes soda bread with sunflower seeds 
included and uses kefir (middle eastern fermented milk). When just 
cooked sunflower seeds look normal but over a day or so many turn bright 
blue-green. Pigment is not water, oil or acetone soluble and is reduced 
with alkaline dithionite (Like indigo !).

Same bread with yougurt does not show the effect.

Any ideas ?

Peter Harris
Reading, UK.