Roggenmischbrot - today's bake

This came out of the oven yesterday and it rested 18 hours before slicing.  60% flour weight whole rye, 40% white unbleached all purpose.  Tom Cat's formula from this site.  The poolish had 12 hours at room temperature, the bulk fermentation was 4 hours refrigerated, and the final proof was an hour or a little more in the microwave with a cup of hot water.   Baked for 1 hr 5 minutes at 405F.   18 hour rest before slicing.  Finished loaf weight around 1.7 kg or so.

I liked the oven spring, color and aroma.  The crumb looks "rye-ish" to my eye.  Ate some this morning toasted with butter and honey, it was good.  

Need to think about adding acid, or not, as I have read about adding acid (lemon juice, vinegar, etc.) to rye breads.  To my taste I am not looking for a modified or different flavor, but because acid seems to be a common ingredient with rye breads I will try it.