Yesterday, I took regular baking soda and baked it for half an hour 200°C, wow, did that increase the strength! Plan on dissolving as much as I can in a shallow glass or plastic non-reactive pan of cooled (boiled) water and using this water to soak shaped rolls for about 10 to 20 minutes of the proof rise.  Remove and place onto baking parchment or well greased pans, score before bake.  They brown like crazy and take on pretzel taste.  (I've made thin wormy pretzels but my husband ate them faster than I could bake them!)   A great bake to watch and don't let the darkening scare the crap out of you!  Use a stiffer dough so it doesn't fall apart in the soak.  Heat up the soda soaker when done (vacuum pack in glass jar) or simply save and refrigerate for the next time.  Add more of the baked soda and water as needed.  (Do not use the baked soda as "baking soda" after this, it is too strong.)  Stir up before using again at room temp or slightly warmer if speeding up the rise.  Can use your fingers and a slotted plastic spoon.  Rub hands in a very thin vinegar solution after playing (under 5%) and rinse.