I've been baking a buckwheat sourdough for 6 months using KA special flour and 10% buckwheat.
825g KA special
mix 2 minutes, add salt and autolyse 15minutes, mix 2 minutes. Proof twice, shape and refrigerate overnight. Baked in a cast iron oval roasted at 450F 20 minutes covered, 20 minutes uncovered. The results were good; tight crumb, good crust, perfect vehicle for mopping up sauces.
However, I developed an allergic reaction on my hands to the KA special which a professional bread baking friend suggested was the fungal amylase present in all (or most KA flours). Very small kitchen space limited my flour allotment to one, which I could use for sweet and savory pastries and KA special seemed to fit the bill, save for the incediary itching on my fingers.
I got some Giusto's la Parisienne to substitute for the KA and after the same proceedure the loaf was flat and whitewashed. Awful. It looked fine after proofing in the refrigerator at the end of the night and in the morning looked like it had been sat on. I mixed 3 minutes rather than 2 and the crumb held a slightly better.
I tried a 50/50 KA/Giusto's and the results were a bit better.
Any suggestions, advice or answers as to why the results were so different? More kneading time or change in hydration?