Testing limits and learning
I wanted to test a Bosch Universal Plus that I have repaired so I put together a Vermont Sourdough - Rye test that consisted of over 13 lbs of dough. The mixer handled it but I will not do it again anytime soon. For one, with that much dough I never felt fully in control with the mixer. The dough was good but sticky throughout all the operations. I folded the dough twice at 50 minute intervals but it was still a bit slack.
I also increased the oven temp to 425F to try to increase browning. I misted the inside of the oven twice during the first ten minutes for moisture. The crust is still lightly colored. My slashing technique is still hit or miss. Both racks of the oven were in use to accomodate 8 loaf pans. No room for other moisture techniques.
My next plans with this recipe are to increase the heat to 460F as is called for with baguettes in the recipe. I will only bake two loaves. I really just wanted to see if I could do eight loaves and if so, what problems would arise. The dough was touching the top cover during the kneading. Getting the dough out of the bowl was challenging. I could not even see the dough hook. These are the kinds of things frequently left out in the promotional videos.
It's always good to learn the limits of ones tools. I'm surprised that machine was able to mix that much dough at once, in spite of the problems you noted. I reckon there are four data points that are useful. The smallest and largest amounts of dough it will mix, and the upper and lower limits of optimal amounts of dough. I guess defining optimal amounts might be a bit difficult and subjective....
I also learned that Bosch Universal has a greater dough capacity than the Haussler Alpha. I got this info from the folks at PHG. While I would not normally do this much dough at once, I did find homes for 6 of the loaves at work and kept two for myself. My co-workers like sourdough and they liked how the loaves looked.
I'm set to sell off a motorcycle on Saturday. If that goes through, I'll get a new mixer. I would have done it today but I had to go to work to fill in for a co-worker. The price of the Haussler is still nagging me but even with the price I think I prefer it to the Ankarsrum. I keep seeing notes about the Ankarsrum's high learning curve.
As for an optimal amount. In my case that would be about ten pounds in the Bosch. Once I learned to handle that comfortably it could probably increase a bit but that seems plenty for my Bosch. When I have to search for the dough hook I'm beyond where I want to be. It was difficult to get 13 lbs of dough out of the bowl. It was heavy!