Here is the crumb of my latest sourdough whole wheat toasting bread. This is a 90% whole wheat/10% white AP flour (from my starter) and 70% hydration, so given my tendency to make the occasional whole wheat “brick”, I am really happy with this. This with zero yeast.
It tells me that my starter is very active, and the flavor is very nice. Plus, as many people will tell you, sourdough whole wheat has a lot of character — both in flavor and in the nice chewy texture of the crumb. The basic idea is that sourdough brings a range of bacteria, enzymes and wild yeasts that work on the flour, breaking down its complex carbohydrates and releasing lactic acid.
This was a three stage loaf, with an overnight pre-fermentation (without salt), and then a day-long fermentation (including some time in the refrigerator) with the finish flour and salt.
My sourdough journey will continue!