The sampling programme at 13 UK milling plants follows reports that wheat flour may contain traces of soy, the agency said.
“Previous studies have shown that soy may be present at low levels in wheat flour. A 2013 survey carried out by the National Association of British and Irish Millers showed that low levels of soy were present in 15 out of 45 samples,” it said.
It said that it believed soy in flour was unlikely to pose a risk for people with allergies and would not require precautionary labelling.
Nonetheless, the tests would gather further data on these levels in order to assess this risk and ensure consumers were being given accurate information about flour and flour-based products.