Renewal Mill is a company that produces “upcycled” flour products (and baked goods made from them). Upcycled products are those derived from would-be waste byproducts, i.e., materials that would normally be thrown away after the manufacturing of something else. Renewal Mill currently sells two upcycled flours: one from okara, or the pulp leftover from soy milk/tofu production, and another from the pulp that remains from the creation of oat milk. (They also produce numerous baking mixes incorporating these flours.)
Renewal Mill’s flours are made by drying and milling the insoluble components of their starting products, which means that some of the nutritional value of the oats or soy are no longer present in the flour, since they have already been extracted into the oat or soy milk. That said, there are plenty of water-insoluble nutrients in grains and legumes, especially fiber and protein, along with minerals like calcium and potassium, which means that these flours retain plenty of value as foods. Moreover, by using them in place of a first-use product like wheat flour, it can have a positive impact on climate change, since it reduces the overall energy input of the process.
The folks at Renewal Mill approached me recently to develop bread recipes using these flours, and I was excited to see what I could do with them. We recently switched to drinking oat milk at home instead of dairy milk, so the idea of reducing the amount of waste involved in its production was interesting to me. Which is why I started experimenting with the oat milk flour.
And I love a challenge, which in this case involved seeing just how much of the flour I could cram into a loaf of bread before its texture took a turn for the worse. Oats are not related to wheat and don’t contain any gluten. And some of the sticky proteins they do contain—compounds called avenins—are what makes oat milk milky, so they are removed during its production. Which is why I knew that adding too much oat milk flour to a bread could compromise the structure of the loaf.
But I figure if you are going to add anything to a bread, especially one that is supposed to be good for you and for the planet, you might as well try to get as much as possible into the recipe, otherwise the exercise would be ultimately meaningless.
As for what recipe to use it in, that was obvious: something with oats in it already, and preferably a sandwich bread that would be nice with the close crumb that a gluten-structure-compromising ingredient would produce. Thus I decided to adapt my oatmeal maple porridge sandwich loaf to use oat milk flour alongside the rolled oats. Additionally, I converted it to a yeasted bread, since I figured many Renewal Mill customers might not be sourdough enthusiasts (yet).
Since the recipe is a porridge bread, it made sense to see if the oat milk flour could be incorporated into the porridge, which would allow it to do some of the work of holding onto the water in the loaf to make and keep it soft and moist. I wasn’t sure if the oat milk flour would still have the ability to bind water, given that it had already been processed, but was pleased to find that it did. (The mixture starts out loose but quickly tightens up as it sits.)
In the end, I was able to add 60g to a standard 9x5 loaf, or about 1/2 cup. While that is a respectable 20% of the total flour in the recipe, 1/2 cup didn’t seem like a whole lot to me—it’s about 1/10th of a standard bag of oat milk flour—but it’s comparable to what many of the other recipes on the Renewal Mill website use, and most of those are products like cookies that need far less structure for success. And though it isn’t a lot of oat milk flour to use in a single recipe, there are plenty of other options for what to do with the rest of that bag.
I will say that the road to a solid recipe using oat milk flour wasn’t without its pitfalls. It definitely compromises the gluten structure in the dough, and I had plenty of loaves that seemed like they were going to be lovely, only to have them collapse during the bake or as they cooled (what I call the dreaded suck-in). In order to minimize this, I found I had to take care not to over-strengthen the dough, lest it want to grow too tall in the oven and not be able to support itself once its final height was set.
This was a bit counterintuitive to me: Normally when I want to gird a loaf against collapse due to some other gluten-compromising element, I make sure to maximize the structure of the dough by kneading it in a machine, adding folds, choosing bread flour over something with less protein, etc. Here I found that a too-strong dough tended to grow overly tall in the oven, only to implode once it cooled. When instead I hand mixed the dough and gave it only a single fold during the bulk proof, the the overall stature of the loaf stayed modest enough to avoid disaster.
I hope you’ll give Renewal Mill flours a try, especially in this recipe. (I think it is just as nice as the original oatmeal sandwich bread recipe.) You might be able to source Renewal Mills flours locally using this store locator. If not, you can order it from them directly on their website, and when you use the code RMFLOUR20, you’ll get a 20% discount off of the retail price.
And while I really do want you to make this recipe with oat milk flour, you might note that I mention in the recipe that it can be made without it by just increasing the amounts of bread flour and rolled oats, which means it doubles as a yeasted version of the oatmeal sandwich bread recipe too.
You can find the new recipe here: Oat Milk Flour Sandwich Bread. (As always, please comment on the post if you notice anything off or in need of more detail and I will correct things ASAP.)
Read recently that Chinese steamed bun dough is sometimes made using soy milk "leftovers", will give it a try and see how that works out. I personally add it (together with the soy milk) back into my morning porridge on a daily basis.