I am new to using sourdough and I am trying to find out how much sourdough I would need for my family's needs. I have 6 kids and do a large batch of no kneed bread dough twice a week that I can bake 2 loaves fresh every day. This batch would use 4 cups of sourdough. All the instructions I have found talk of using the sourdough starter once a week. Does the starter stay strong/healthy enough to use more frequently or should I keep 2 starters going?
Just keep it fed and it'll be good. Frequent use = frequent feeding, and starters like that. Trouble usually comes when it doesn't get used regularly and doesn't get feed regularly. Once a week bakers, like myself, get by by keeping starters in the fridge, or keeping a very small amount to start with, and feeding regularly with a small amount until we build up enough for the bake. I'll just add - you have 6 very lucky kids!
It's probably better to go by weight rather than volume, since the starter volume will change as it expands, but not the weight.
In my case, I generally use either 100 or 120 gm per bake. I keep 150 gm, which means that I have either 50 or 30 gm left, which I then top up by adding equal weights of water and flour. In terms of baking again the next day, my starter is ready a few hours later, at which point I put it in the fridge until it's time to use it again. When I don't bake again for a few days, it's still fine.
Here's what I do. I build a relatively dry starter once a week, following a 1:2:4 formula I got from Trevor Wilson. After letting the starter build overnight I refrigerate it for the rest of the week. In my case my weekly build totals 350 grams (50 starter, 100 water and 200 AP flour). I call this the mother.
If I am going to bake on Monday morning, on Sunday morning I will take a piece of my refrigerated mother and use it to build a refresher. The composition of the refresher will generally reflect the composition of the bread I am going to bake on Monday, and it totals the amount of starter that I will add to make a levain on Sunday night. So, if my levain calls for 50 grams of starter I will make a 50 gram refresher on Sunday morning. This might be composed of 10 grams of the mother, 17 grams of water and 23 grams of flour (75% hydration). If I keep the refresher at around 75 F, by Sunday evening the refresher will have doubled, or close to it, and I will use it to build the levain for my final mix. The levain sits at around 75 F and essentially doubles overnight. By using this method the small amount of mother I pluck from the refrigerator gets a kick start to reactivate the dormant cultures through the refresher process.
I will do this over and over again for about a week, then I will build a new mother. The fact is that the mother will last quite a bit longer than a week in the fridge, if you choose to maintain it that way. I have been doing this quite successfully for some time now.
Jim