Nah.
I mean, after all, it's just flour and water, right? It may be bubbling a bit, or it might just be sitting there being sad and unresponsive. But it's just flour and water with not enough wild yeast to give your bread a rise. Because if it was active, you'd be using it for real sourdough bread, right?
Lately I've been experimenting with sourdough cultures, trying to find the ultimate method for growing a culture with the least amount of fuss and the least amount of waste. But that experimenting has resulted in a lot of excess starter that's not quite ready to work on its own. There's no way I'm going to throw away food that I can find a use for, even if it's just flour.
Unfortunately, my recipe for using that leftover starter it is less than precise. It has to be that way, though, because there's no way to predict how much starter you'll have to dispose of, or how wet that starter might be.
But here's what I did:
I dumped the starter - a little over a cup - into the bowl of my stand mixer, and added enough liquid to get it to the consistency of a loose cake batter. Normally I'd add water, but in this case I added some apple cider to give the bread a bit of sweetness, and just a little bit of milk to soften the crumb. If you're making it, all water is just fine. I've said before that you should scald milk before adding it to bread, but I didn't use much - maybe two tablespoons, so I wasn't concerned.
I added enough bread flour to turn it into a dough. I've made enough doughs to know what my usual amount of dough looks like, and I typically bake single loaves of bread that have roughly 12 ounces of dry ingredients and 8 ounces of liquid. For that amount of flour and liquid, I typically use 2 1/2 teaspoons of yeast and a teaspoon of salt. This lump of dough looked pretty typical, so I added two teaspoons of instant yeast and 1 teaspoon of kosher salt.
I kneaded it with the dough hook until it was silky, stretchy, and smooth, then I added some olive oil - maybe a tablespoon or so. I kneaded until that was incorporated, then formed the dough into a ball, coated with a bit more olive oil, and set it aside to rise in the stand mixer bowl, covered with plastic wrap. It took about 2 hours, but that's will vary depending on your particular dough. A proper rise is more important than how much time has elapsed.
I kneaded the dough again, formed it into a ball, and put it on a cornmeal-sprinkled baking sheet. The oven was already heated to 350 degrees from a previous loaf of bread, so I left it there. I let the dough rise until doubled - about 45 minutes (typically the second rise is half the time of the first rise) then slashed it and baked it at 350 degrees for about 40 minutes.
There's no way I would call this bread "sourdough," since it used commercial yeast for rising. But because the proto-starter had developed flavor, the resulting bread was more complex than a typical loaf of white bread. The experiment was a success.
And here's another yeast/sourdough hybrid.
This has been submitted to Yeastspotting.