Refreshing your sourdough starter
In a previous post I wrote about starting a levain culture. If you’re not planning on baking all the time with your sourdough starter, in between uses, you can keep your starter in the fridge.
When I’m done making a levain bread, I put the entire container of culture in the fridge and leave it until I next want to bake, when I go through the refresh process. The container is pretty big though (in warmer seasons you want to have plenty of room for the levain to bubble and expand without overflowing – trust me! There were a few mornings during summer when I came downstairs to discover a puddle of escaped levain all over my kitchen table and floor and it’s a real pain to clean up!), so if you don’t have room in your fridge Ken Forkish recommends in his book Flour Water Salt Yeast: The Fundamentals of Artisan Bread and Pizza that you can decant 300g of your levain into a plastic bag / smaller container, coat it with a thin film of water and refrigerate.
Step 1: two days before you want to bake
Two days before you want to bake, take your levain out of the fridge and let it come to room temperature for between half an hour to 1 hour. Retain 200g of starter and discard the rest. If it has been a while since last baking with your levain you might notice some changes – the top of your starter might have darkened in colour and there might be a bit of surface liquid that smells very strong and alcoholic. The starter might also have changed consistency and become like a paste. All of this is normal; tip any surface water away and the process of refreshing your levain with fresh flour and water should restore it.
Give your remaining starter a feed with 100g wholemeal flour, 400g white flour and 400ml water (at 35°C).
Give everything a really good stir, trying to incorporate any dry flour pockets into the dough and scraping up any flour that may be caked on the sides of the container, pop the lid on and leave it in a warm spot overnight.
Step 2: the morning of the day you want to bake
Feed your levain again. Discard everything but 100g of the levain. At this stage, you can bake with the discard – I pop it into a separate Sistema box, and stick it in the fridge to use in other recipes. Add 100g wholemeal flour, 400g white flour and 400g water at 29°C to 32°C, depending on the season.
Mix by hand until everything is incorporated, then cover it and let it rest in a warm spot until you mix your dough later that day. After overnight bulk fermentation or proof, depending on the recipe, you will be ready to bake the next day.