Looks tasty! I’m a sucker for buttered and toasted sourdough or rye.
This culture isn’t nearly as sharp as a San Francisco germ
Apologies if this is obvious to you, but IIRC from past reading, commercial sourdough achieves a higher acidity without needing to use the specific yeast via just adding acid directly. If you aren’t dead-set on authentic, “the yeast do everything” sourdough, you could probably tweak sourdough to taste that way.
kagis
Okay, this isn’t talking about what commercial producers do, but it is directly talking about increasing tang in homemade sourdough via the “directly-add-acid-to-the-dough” route:
How To Make Sourdough More Sour: A Guide To Getting More Tang In Your Bread
Learn how to make your sourdough more sour depending on your personal taste. You'll learn what makes sourdough sour and how to make your sourdough tangier.
The Pantry Mama (www.pantrymama.com)
Use Citric Acid In Your Sourdough
If you really want a stronger flavor in your sourdough bread, adding a little citric acid to your dough will help.
You can add ⅛ to ¼ of a teaspoon of citric acid to your sourdough. Do not use more than this amount because it will make your sourdough inedible.
You add the citric acid to your dough along with the water, flour and salt.