Using pastry flour for standard sourdough bread recipe?

Question

I am trying to make sourdough bread, but was only able to get whole wheat pastry flour (due to covid). Characteristics of this flour (from Bob's Red Mill) are: 1) low protein content 2) stone ground 3) super fine/densely milled. So far, my results have been very bad: both starter and dough are rising very slowly, and after reshaping, dough will not rise much. Standard (i.e. not for pastry flour) recipes I tried so far are:

1. Sourdough focacia
2. Beginner sourdough bread

How can I do to use this pastry flour for a sourdough bread? Are there specific recipes? Any parameters I should adjust, such as water content, rising times, starter feeding, etc?

Thanks!

Answer 1

I have been making sourdough bread with a few kinds of flour. In my experience, bread flour (higher protein) really does make a difference in many qualities of bread that you look for -- texture, rise, chew, etc. However it is incremental, maybe like 10-25% better, so it should still be possible to create good bread with lower protein flour.

I can give a few tips for your starter that I recently learned. The starter should be at least doubling if not tripling or quadrupling in volume each time you feed it. When I feed my starter I add 1/3 starter to 1/3 fresh flour and water. So for example if I have 100g of starter, each time I feed it I take 33g of that starter (discard the other 67g) and add it to 33g of each flour and water. After 2 or 3 of these feedings it at least triples in volume each time. If it is sluggish, I make sure it is in a warm spot, ideally about 85F. There can be a big difference in activity between this and a cool room temp of 65F.

Also the starter should be peaking in activity at the time it is added to the dough. For me that's usually about 3-4 hours after feeding but it depends. If it has fully deflated before you use it the activity will be less.

Something I have started doing is overnight fermentations of the dough, usually about 18 hours, at room temp. This results in bread that is much more sour and has a wetter, stickier texture that I like, so might not be for everyone. However it makes it easier to get a good rise. My dough will double or triple in volume overnight and there is not much harm in having it sit for a few more or less hours. The activity and strength of the starter matters a bit less because it sits for so long. When I'm ready to bake, I will "stretch and fold" the dough and it usually rises back up within an hour or two and is ready to bake.

Answer 2

The issue is the protein content of your flour. For bread recipes, you typically want higher protein for the development of the gluten structure. Bread flour can be in the 13 to 14 percent range. Whole wheat pastry flour has a protein content around 6 to 7 percent. If you have access to vital wheat gluten, you can use it to increase the protein content of your pastry flour. It won't be the same as using bread flour, but it will be better than using pastry flour. This question will help get you in the ball park.