Well, all I know is that yeast doesn't produce comparable results, when baking rye-based breads.
Ha ha somehow I knew we disagreed about the taste!  Rye-based breads use biological leavening just like sourdough.
My friend has been sending me pictures of all the baked goods she has made recently. She must be so talented to be a baker! Does she bake bread? I know that the Gauls discovered that beer froth made well-leavened bread. Yes, but I don't think she has ever used beer froth before! Can you tell me more? I don't really know more. What I known is that there is a process know as fermentation That is really interesting. I've had fermented cabbage and it's delicious. What other types of things can you bake? I can't name any others. Have you ever tried sourdough bread? It is made using naturally occurring yeast and lactobacilli I guess opinions will vary, I love sourdough bread! Do you know how they make rye bread?
It is important in baking rye-based breads, where yeast does not produce comparable results.