Cottage pie that was delivered to 47 schools in Lancashire has tested positive for horse DNA.
The product has now been withdrawn from kitchens.
Officials at Lancashire County Council say the amount of horse consumed by the children will have been 'minute.'
Analysts at one of six laboratories in the country doing the FSA's tests discovered the contaminated product late yesterday.
Scientists uncovered equine DNA at 0.1% concentration in samples.
Headteachers have been alerted.
More top news
Changeable and chilly into the new week with sun and showers - and a very breezy Monday afternoon
The new week promises to be a little vexing - a real mixed bag and rather changeable
A bright start to Sunday - a much fresher than Saturday. Cloud slowly bubbles up, dry for much of the day, but shower later