Maybe a hybrid tecnique?
But if the microbes is really Clostridium perfringens can it co habit
with the bakers yeast to make such combined fermentation feasible.?
I am not familiar with the pH optima of such bacteia but yeast thrive
in slighty acidic conditions.
Have you tried inoculating your salt rising dough recipe with bakers
yeast and what its the results? That may help you answer the puzzle if
the bakery you queried is doing a related technique.
Its unfortunate that SRB is not part of my baking interests.
BTW,I heard that there are bakery ingredient suppliers that supply salt
risimg bread premixes. I think that would answer the question why
Heinzman are reluctant to divulge more information as they are not
actually doing the 100% salt rising bread..
And they maybe right ,they are maintaining the use of such SRB
simulated mixes for years<g>.
Roy