I have a beloved sourdough started from yeast and bacteria captured in southeast Michigan.  I usually store and feed it as a liquid (equal weights flour and water) and convert what I need into a stiff starter two days before baking.  I’ve had very good luck with most of the Bread Bible sourdough recipes and with replacing 30-40% of regular bread recipes with my starter.  I’m very happy with the rise, crust, crumb, and flavor of my breads, but it is a very rare that any of them taste appreciably sour.  Does anyone have any recommendations for coaxing some significant sourness out of a mild-mannered starter?

I’m glad you asked this question.  I noticed the same thing with my own starter, using Nancy Silverton’s liquid starter formula.  It produced perfect bread in every way except for the noticable lack of sour tang.

I look forward to hearing the responses.

I too followed N Silverton’s instructions but my starter was very sour. I used some orange peel to inoculate my starter.

If you let the starters ‘ripen’ for a longer time in warmer conditions you will get more tang to the sourdough.  The yeasts grow quicker than the bacteria (which is acidic and gives the sour taste) so if you make the bread before much of the bacteria multiplies the bread will not taste sour.  Taste your ‘mother’ and see how sour it is.  It’s probably quite sweet.  As an experiment, make a liquid starter and leave it at room temperature.  Every few hours taste it.  You will actually taste the acidic development as the hours go by.  Rye and wholewheat seem to sour quicker than white flour, so you could try with one of these flours.  I have never added anything to my starter other than flour and water and I can control the sourness of the breads I bake just be time and temperature.  By the way, if I want a very sour bread I make it over 3 days.

What Annie says makes sense. I was feeding my starter twice a day but not discarding any. When I developed about a liter of starter I would bake with it. I always kept it at room temperature.

Ah, the longer warm temperature ferment could be the answer.  My starter lives in the fridge.  I double (or quadruple) it overnight two nights before the baking, refrigerate during the day, then feed again the night before baking.  I’ll skip the refrigeration step next time to see if it ends up more sour.

If I want a more sour bread, I let my starter sit for double the amount of hours during its first and sometimes second expansion, for bread baking.