maintaining your sourdough starter
Think of your starter as a pet, or perhaps as a herd, because that’s what it is—millions of bacteria and yeasts living in a little jar! They don’t ask for much, and they’re happy to help you with your baking. Nice deal.
You’ll want to feed your starter every day. Here in the bakery we feed ours twice a day. The important thing is that your herd needs a regular schedule; they don’t like to run out of food, and they don’t like being swamped by too much food all at once.
Here are some practical recommendations: keep your herd small. Each day, cull 85% of the herd, and replace it with rye flour and cool water. The exact amounts don't really matter much. Just provide a moderately loose mix with sufficient fresh food and sufficient water for your herd to thrive. You will see, as you gain experience, that the way you care for your herd changes the way they work and reproduce. A wetter mix, for example, will generally speed up your herd’s reproduction, and of course, they will eat through your feed a little faster, too. Warmer temperatures will accelerate things as well.
You will want to take care to use water that is approximately 65F-70F. I am sure, now that you are taking your temperature every day, that you realize that this feels COOL. Not warm. You can speed up reproduction with warmer water, but our experience shows that your starter will not necessarily be stronger for that, and your flavors can go off. Best is a steady and moderate temperature—neither too hot nor too cold. If you want to get specific, we keep our starter at 65F all day and all night. It really likes that.
At the bakery, we use our starter every day, so it lives on the counter and gets fed regularly. When I did most of my baking at home I kept my starter in the fridge, and because sourdough microbiota slow down as they colder, that meant I didn’t have to feed it every day. But that also meant that I had to wake up my starter the day before I started baking. Baking with sleepy starter is no fun, and it’s a good way to end up with “bricks” that are too heavy even for squirrels. So, if you’re going to put your starter to sleep in the fridge during the week, be sure to take it out early. Let it warm up and give it at least two good feedings before you start to bake with it.
It is important to use your starter when it is at its peak. When you feed your starter it quickly begins to ferment. You can see it. You will see the mix swell and bubble. Over a period of 8 to 12 hours the mix will go from a smooth and dense paste to something almost fluffy. You will see bulging on the top of the mass, and you will see the character of its surface change. If we were to ferment this mix in a glass jar, we’d see it rise and swell, reach a peak, and then recede. That peak is what you’re looking for!
If you use your starter when it is too young or too old, your dough will ferment too slowly, and the dough will be difficult to handle and the bread will have poor flavor, color, and rise. One of the most important arts of baking is TIMING! You will have to figure out when to feed and use your starter in the context of your life.
Let me give you an example: In the bakery, we need bread on a Friday morning. That means we need our doughs to be fermenting well by Thursday at mid-day. That, in turn, means that we’ll need an appropriate amount of the flour to be at its peak fermentation on Thursday morning, and that will require that we start that fermentation late in the evening on Wednesday. In order to assure that the fermentation gets off to a good start on Wednesday, we need to be sure to feed the starter around mid-morning on Wednesday. We bake a lot, and we feed our starter every day such that it is ready to use in the late evenings when we begin the larger fermentations.
How to put your starter on hold:
Your herd is lively and demanding, but they’re on your side. If you ask them nicely, they will happily take a long nap while you go on vacation. All you need to do is feed them well and then chill them down by putting them in the fridge. Your herd will last almost indefinitely in the refrigerator. As your starter gets older, sitting there in the back of the fridge, it will start to look pretty nasty. It will likely turn black and accumulate a layer of clear liquid. Don’t be scared. It is not dead. To revive it, pour off the “hooch” and scrape a little hole in the skin of the paste beneath. Then take some of the material from the center of the paste and mix it, in a clean bowl or jar, with a small quantity of flour and warm water. Let it sit for 8 hours, then add another quantity of flour and warm water. Wait another 8-12 hours and begin a regular feeding schedule. It’s possible for your herd to die, but it doesn’t happen often. You may hear folks talking about how they “killed” their starter by ignoring it, but I think it’s more likely that they thought it looked too nasty to work with… so they threw it away.
And even more!...
I gather there is some confusion about how to keep and use that starter.
Let’s talk about it. And we’ll have a brief discussion about how to use it to make bread.
As you know, I’ve posted some instructions for you on the website under the “hand” tab, but I gather more specificity would help.
So.. here we go.
Your little dollop of starter! It’s a herd! I made it dry and cool for you, so it’s growing very slowly. If you put it in your fridge, it will keep like that for a long time. If you want it to do some work for you, you will need to do three things: 1) give it a drink, 2) give it some warmth, and 3) give it a meal. Think of it as taking your starter to the pub.
In practice, you can get it going like this: Take the whole thing I gave you—dollop and flour—and moisten it with room temperature water until it is a gluey paste. Then let it sit at room temp for four hours or so. You will see it grow and change. It will get fluffy, and it will start to shine. It will bulge. It will expand.
After 8 hours it will start to sag, and it will lose its shine, and it will smell different. At first it will smell like like apples, then like older apples, then like old apples and some other weird things, and then like very old apples and vinegar.
If you have time—and these days who doesn’t?—you could get your starter going in a glass jar and film it with your cell phone. You’ll see all the changes happen, and you can clock them. If you keep a piece of paper nearby, you can also smell it every 20 minutes and keep an aroma log. Besides being fun, this little science experiment will make you a MUCH better baker. If you have kids at home, let’s just say… it’s a lot better than school!
OK! Now you’ve met your starter and seen how it does what it does. Now you need to know how to feed it! it’s easy. Just throw away half of it and add a quantity of flour, then mix with water to form a gluey paste.. You’ve been here before. Easy, right?
If you want to put your starter into hibernation, just mix it fairly dry and put it in the fridge. It will last forever.
Now. I hear you cry. How do we BAKE with it?
I will give you a VERY simple way to do it.
To do this easily and well, you will need a SCALE.
Weigh out the following:
A tiny nub of starter. Like.. as big as half a small crab-apple, or as big as your pinky fingernail.
Those are ALL your ingredients!
First, in the evening, take 15% of your flour (that’s 150g) and put it in a bowl.
Add to it an equal weight of water (150g) and the nub of starter. (Bonus question: How much water do you have left to add to the dough?)
Mix it all up!
Go watch a movie.
Have a glass of wine.
Let the glop sit overnight!
In the morning, your bowl of glop should be lively. Mix it with all the remaining ingredients in a larger bowl.. you can use a mixer if you want.. and make sure all the flour gets wet. It should look “rough” and “shaggy.” But no lumps of dry flour! It will NOT be “smooth like a baby’s bottom” or whatever it is that people go on about.
Move the shaggy dough to an oiled container that’s big enough to let the dough grow, and cover it. The oil makes life a lot easier.
Every 40 minutes or so, you are going to “stretch and fold” the dough. It’s easy! Just grasp the dough on the North side, lift it up 8” or so, pull it across the rest of the dough, and lay it down. Now do the same to the South side. And now the East. And finally the West. That is ONE turn. So every 40 minutes you do that.
After three hours or so, the dough WILL be smooth like a baby’s bottom!
And it will feel alive and probably gassy! Like a baby’s bottom.
Take your dough, shape it into a couple of pan loaves, or make a big round, or do whatever you want with it. Then cover the imminent loaf and let it sit in a cool place. Your fridge will work, but it is really cold. Let it sit there overnight.
In the morning, bake your bread!
You will have to make all kinds of adjustments to suit your own place and schedule. Just remember: warmer=faster, cooler=slower. If things are moving too fast and your dough seems way too gassy and it falls flat in the oven, make it cooler or bake it sooner. If your dough seems dense and lifeless, and it doesn’t do much in the oven, make it warmer or bake it later. If everything about this feels too fast, you can use a smaller portion of the flour in that first overnight fermentation. If it feels too slow, you can use a larger portion. Some guidance: 10% is slow (12-24 hours usually), and 30% is pretty fast (bake the same afternoon).
For those of you who wrote asking for “recipes,” this is THE ONE! You can mix flours.. you can add more water.. but basically, this is it. Not joking.
One note of caution: That quantity (note that it is really a ratio) of SALT.. don’t mess with that. For more on salt and bread, you can read this.
That should get you going!
With great affection and optimism for your baking adventures,