Subject: 20. How much starter do I need to keep?
I think the important point in the Silverton procedure is to frequently feed the starter so that it as active as humanly possible. I think she committed a major screw up by stressing the volumes so much. Thus it would be perfectly OK to start with 1/2 a teaspoon of starter and add 1/2 teaspoon water and flour and on the next feeding double this to one teaspoon, then two teaspoons, 1/4 cup, 1/2 cup etc until you have the amount of starter that you need for your recipe and a little extra to store. The doubling procedure is standard practice in most sourdough recipes but there is no law saying you have to double. In fact, some German recipes start with a massive dilution (one in 100) for the first feeding and then use the normal doubling until the required amount of starter is built up.
A single teaspoon of active starter (or starter stored for a few weeks at most in the fridge) will have tens of millions of yeast/lactobacilli. It is thus not difficult to rebuild the starter from seemingly vanishingly small amounts. A thick head of bubbles will tell you that you starter is chugging along. Of course this assumes you have a good starter to begin with - if you do not have a decent starter then the frequent feeding regimen recommended by Silverton will rapidly lead to death of your starter(?) because there simply were not enough organisms to double at the same rate at which you feed them.
The important point if you start with small volumes is that the starter can dry out relatively easily - you have only 1/2 teaspoon or one teaspoon of water to evaporate in the early steps. Thus you should take steps to ensure that the starter does not dry out - make it a bit more wet than normal, for the first few feedings cover it with a wet towel or place it in a glass which in turn is placed in a rubbermaid container filled with a little water. In the cold weather I use small coolers that I fill with water at the right temperature (85F) and then float my starter on rubbermaid boats in there - this serves as an incubator and also keeps it relatively humid.
I am astounded that a celebrated chef like Silverton could suggest a recipe that would end up with 7 pounds of starter that you have no use for! This convinces me that all cook book authors seldom actually test their recipes or check for appropriateness for their audience - Silverton's recipe would be fine for a bakery but ridiculous for the average Joe or Jane that the book was written for.
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