Some good reading here about how the supermarkets are, yet again, bodging our foodstuffs by pushing for a widening of the definition of sourdough so they can make it easier (and cheaper?) to bake and include various other 'agents' to 'enhance' it.
"We have no problem at all with a supermarket selling genuine sourdough. Just don't cheat, don't fool people," said Chris Young, co-ordinator of The Real Bread Campaign.
Independent bakers say real sourdough should not contain baker's yeast; the whole point is that we use natural yeasts.
I have heard of and used the term 'semi-sourdough' myself, so maybe that's what should be used, so it's clear that's what it is if dried or bakers yeast has been used in the mix.