Baking Under the Az Heat Dome: Detmolder 2-stage rye starter

As this Arizona summer has been blistering 115F, I've been struggling adapting my old baking ways. I've always used flour out of the freezer and cold water; I've always cut times and inoculations. But even with all my tricks, I'm running into degraded dough. I can adjust the yeasts but I'm thinking the lactic acid and protease builds very rapidly in the high heat.  But shortening alone doesn't give me the flavor I want. As I slowly gain control, I'm going to share any successes, for the benefit of others struggling with the "new normal".

Today I needed 224g of a mature rye starter to make a bread by Hamelman. In Bread his usual rye elaboration is to mix an 83% rye levain with a 5% inoculation of mature starter (i.e. 1:20:17--118g of flour) for 14-16 hours at 70F.  With adjustments this works iTucson winters for me but not now. 

Reviewing my notes on rye, it jumped out that the 2-stage version of the Detmolder process was ideally suited to my blistering temperatures, like a glove. The 2-stage Detmolder reduces the more :"regular" three stages to two rather warm stages: 

• a long stiff phase -- bring out acidic bacteria.
• a shorter moister warm phase -- bring out the yeast and lactic.

I've seen various renditions, but this time used the guidance from homebaking.at's "pumpernickel master class" as my template, https://www.homebaking.at/en/pumpernickel-mit-feinem-schrot/ :

What attracted me was the relatively warm temperatures of both phases, the acid phase and yeast phase. Instead of Hamelman's 70F, the long ferment here was at 77f (close to the temperature in my house) with a booster refresh at 82F (the temperature in my laundry room).  Exactly what the AZ heat dome had given me. 

And I know from experience that super-stiff starters (it doesn't get any stiffer than whole rye at 50%!) are better able to handle heat, with a broader "wiggle room" for maturation. In desert heat, moist starters go bad on you if you answer the doorbell. So being able to produce a hint of that acid tartness without babysitting things was attractive. 

Adapting a bit, I ended up with the following elaboration schedule to produce 242g of starter at 105% hydration over about 24 hours total, using the 1:20 and then 1:2 builds of each phase. (TA and ASG are German abbreviations for dough yield and inoculation, respectively.)

I upped the hydration of phase-2 to 105% from the 90-100% of the original based on instinct, to get things closer to what a liquid white starter would look like. And because my temperatures were a little warmer than the source (78F for phase 1, and 85 for phase 2) I shortened the times a bit, with 17h for phase 1 and 3.5 hours for phase 2. 

This Detmolder-2 worked out really well!  Surprisingly, nothing much happened visually with the very stiff 50% starter during its 17 hours growth. A few small cracks appeared on the ball, but nothing major, and you'd not be a fool to wonder if this whole thing was working. (I'm more used to 85% hydration rye starters where you see "rye islands" on the surface as it expands.)  Putting my nose close, I could smell some faint acidity growing. By the end of the 17 hours at 78F, although there was still practically no visual growth from its start, there was a notable tangy acid taste once I cracked it open. Downside: It took some effort to dilute the hard pieces into the water for the next phase.

Phase 2 took place at about 85F, the current heat-wave temperature of my laundry room. And the bubbles appeared, just as hoped.  By 3.5 hours it was looking just like a mature regular liquid rye starter, sweet smelling and bubbly.  (If I'd dared to place it in the shade outside, I probably could have reduced phase-2 to 3 hours, but one doesn't go outside when its 115F.).

A mature starter with both acid and yeast in warm temperatures.Mission accomplished! 

So--in a nutshell--if you're in a warm climate, consider this kind of elaboration schedule for your ryes. There are other alternatives that might handle the heat, like Manheim salted starters, that I hope to explore.  And what would happen if I just used a chunk of my already acidic fridge storage starter as my phase-1 rather than buildling it? That would save 17 hours.

Next to figure out a workable system for my desem whole wheat starter.