There has been a ban on meat and cheese imports in place for a few months now, from four named EU countries (Germany, Austria, Hungary, Slovakia) where there actually is a foot & mouth outbreak. Extending it to the whole EU makes legal and technical sense in that the EU is one free trade zone, and the salami you found and liked in a Portuguese supermarket might be made with meat from Germany.
The actual risk of FMD entering the UK in cured meat or cheese is close to zero, but the political cost of this sort of ban is minimal and it's probably reasonable (and enables the government to continue its ambiguous approach to the EU; the Tories would be actively trumpeting this as a Brexit benefit). The US and Australia ask if you've been on a farm in the last 7 days when you arrive, which is probably a more likely source of contamination.
Since the risk is so small, I don't anticipate more shifts for customs officers at Stansted pulling people over at random to see if they have a box of La Vache Qui Rit processed cheese triangles.