Category: Basic Starter (Barm)

So asks reader Dean (and Liz, and Darren, and Susan). The answer is a definitive “maybe”. There’s no question that bakers in the Bay Area have the edge when it comes to creating very sour breads. However truly sour, naturally-leavened loaves are possible in other regions of the country (or world), provided you can manipulate your starter’s moisture level, temperature, and rising/proofing times in the right way.

Allow me to explain. All bread starters are tag teams of yeasts and bacteria, with yeasts being primarily responsible for the rise, and bacteria for the flavor. The lion’s share of that flavor comes from acid, which is produced by different types of bacteria in varying amounts. As you might expect, the starter bacteria the thrive in the Bay Area,  L. sanfranciscensis and L. pontis, are world champs in realm of acid production. L. sanfranciscensis produces unusually high levels of lactic acid, while L. pontis makes mostly acetic acid, which is the stuff that gives vinegar its sharp flavor.

Reader Dianne tells me she’s concerned about my mother. She tells me that based on my recent posts, it sounds like I don’t feed it very much, or very consistently. Dianne, that’s true, though I assure you it isn’t a cruelty. The system I use is a little different than most. I keep a very small, somewhat meagerly fed, mother starter. Most of the time I have little more than a cup in the fridge. That’s on purpose, as I like to grow new starters as I need them, not keep bigger ones that require lots of food and attention. Given that the amount of starter you can grow from even a small amount of mother starter is theoretically infinite, I need very little on-hand.

A little-discussed aspect of starters is the degree to which they can be — indeed probably should be — customized according to the type of bread you’re planning to bake. For example, my go-to outdoor oven bread is a pugliese. It’s got a lot of semolina flour in it, which means that in order to get the rise I want from the dough, I need to add a high-gluten (high-protein) flour to the mix.

So far so good. However one key factor is the starter. The starter makes up about 1/3 of the total volume of the dough. My recipe calls for a standard white flour starter. However if I use a white flour starter that I’ve built up (“fed”) using regular all-purpose flour (not a stronger, high gluten flour) then in the end I’ll get a lower-volume loaf, because a significant portion of my flour — the flour that’s in the starter — will be of the lower-gluten all-purpose variety.