The recall comes just a few days after the UK's food agency issued its first ever warning on para red, after trace levels were detected in batches of paprika present in an Old El Paso Mexican dinner kit.
The supermarket chain that recently posted a €2 billion profit for the year, has withdrawn batches of its own-brand 130g barbecue flavoured rice cakes from the shelves bcause they were found to contain Sudan I and Para Red.
Both dyes are illegal under the 1995 Colours in Food Regulations. Sudan I is believed to be a genotoxic carcinogen.
The recall comes as sensibilities to food contamination run high in a country still reeling from the biggest food recall in UK history; sparked off in February after Sudan 1 was identified in over 600 processed food products.
Para Red (paranitraniline red), a chemical used to dye fabrics a brilliant red, is chemically very similar to Sudan 1, said the FSA, advising that although "there is very limited data available it would be prudent to assume that it could be a genotoxic carcinogen."
This latest product recall on a contaminant as yet virtually unheard of in the UK food chain suggests that tougher testing methods will be required to ensure a safe food chain.
It also raises the possibility that Para Red could be hidden elsewhere in foodstuffs; but because previous tests have not hunted for this illegal colour, they failed to detect it.
Unconfirmed reports in the UK press today suggest the FSA will announce a formal plan this week to expand testing to a larger range of spices imported into the UK.
The Food Standards Agency said it may look for the presence of dyes in spices such as turmeric, chilli, paprika and cayenne pepper.