Cold temperature means the LAB are producing acetic acid (tang) and warm means the LAB are producing Lactic acid; Bran acts like a buffer, besides providing all the great minerals and vitamins, in the dough. Bran allows the LAB to continue to produce acid at pH levels that would normally shut down the LAB from producing acid at all. 84 F is the best temp for yeast to reproduce and 92 F is the best temperature for LAB reproduction. At 93 F yeast are reproducing at a restricted rate like it was 44F. So, if you restrict yeast reproduction and promote LAB reproduction you are vastly increasing the LAB to yeast ratio in the starter and dough. More LAB and less yeast mean more acid production over a longer time and a more sour bread because proofing times are extended due to less yeast in the mix. A great SD bread has both tang and sour! This basic science was the foundation of the No Muss No Fuss Whole Rye Starter and how to make more sour bread. You can manipulate the LAB to yeast ratio in starters and dough and you can control the tang and sour in your breads using temperature and science.
Happy Sourdough baking.
Short Crust Bottom and Puff Paste Top for the latest Apple Pie with ginger and snockered fruits with Vanilla Bean Ice Cream