Saturday, January 23, 2010

Sourdough Starter

I'm playing with sourdough starter again. I had one years ago, and used it regularly for a while, then eventually stopped and lost it. I picked up a start again recently, and made a loaf. It was good, but it does take more planning to use, and I don't make it that often. My starter was again in mortal danger.

Then I decided to try making sandwich buns at home, so I can make my own "Texan" sandwich, like at that sandwich shop with the funny-zsky name. Tried a recipe I found online, but it was missing something... oh, sourdough! I'm converting that recipe to use sourdough, and will post it once I have it working right. Meanwhile, I'll post some info I have about sourdough starter.

This is a photo of my starter after sitting out for 24 hours, instead of the usual 8-10 or so. I was going for extra sourness.

This starter was "fed" with half water, half flour by volume, making it wetter than the proper feeding of half water, half flour by weight.

Here it is with the bowl tilted. Note the clear liquid pooling at the bottom, and all the bubbly texture in the thick "batter".

This is the same bowl as above, tilted to show the fermented liquid.

I have seen references to the "water separating out on top" of a starter. This is quite a silly notion. That is not water, and it is not separated like a broken sauce or mayonaise. The liquid is a by-product of the wild yeast consuming (fermenting) the sugars in the flour. This is partly alcohol, and is the "sour" part. More liquid = more sour. Other by-products are carbon dioxide gas, and protein.

You can get a starter from a friend or a store, either wet or dried into flakes. You can also catch one from the air.

Catch a Wild Yeast:
Mix 1 c flour and 1 c water in a bowl until smooth. Leave it sitting out, uncovered, in a spot where things won't easily fall into it, and check on it every day. One day it will either A: Stink and/or look putrid, or B: Have little bubbles in it, and have no change of smell, or begin to have a yeasty smell. If A, throw it out and start over. If B, congratulations! You have caught a wild yeast.

Storing a Starter:
Store starter in the fridge in a glass or ceramic container. The cold retards the yeast growth. Metal is a bad idea, as some of the metal may be leached into the starter. Do not seal the container air-tight. The starter actually needs to breathe. Don't fill the container more than half-way; it might rise and bubble out all over your fridge otherwise. I use a mason jar with the lid screwed on part-way.

For longer-term, or as insurance, drip some onto a piece of plastic wrap and let it dry. Wrap the dried flakes air-tight, and freeze. It will last a long time that way. To revive, use the feeding instructions below, but allow more time for it to get active.

My two starters. The one on the right has been fed more recently, and looks like it rose half-way up the jar while in the fridge. The one on the left has more liquid on top.

Starter Feeding:
1/4 to 1/2 c starter
2 oz flour
2 oz water

Starter has different names depending on the flour/water ratio, such as Biga, Levain, and Poolish. I had been using 1/2 flour, 1/2 water by volume, and then discovered it was supposed to be by weight. The only difference seems to be that it is harder to mix the thicker starter, and the bread recipe needs more water added now. The photos here are from the half-n-half by volume mixture.

Whisk together until smooth, and let sit out overnight, then cover loosely and put back in the fridge. Yes, I use a metal whisk, and nothing horrible happens; just don't leave it sitting in the bowl. The starter will be "active" and ready to use for about 3 days. If you wait longer than that, feed it again before using or it will be extra sour and sluggish. Don't use all of your starter in a recipe; always save out a cup or so to feed and use again later.

Just a week ago, my starter had been neglected in the fridge for about three months. The liquid on top was very dark, and the smell was very strong, almost bringing tears to your eyes. And yet, it did not smell spoiled. I tossed out the liquid, scooped out 1/2 cup of the batter, fed it, and it was good to go. However long your starter has been neglected, if it doesn't smell putrid, give it a good feeding and it should revive.

"Oops, I used ALL of my starter in my recipe..."
Do you still have the jar or bowl that it was in? Even 1/4 teaspoon of starter is enough to build it back up again. Follow the feeding instructions, except let it sit out as long as necessary to become bubbly and active again.