I’ve had a lot of people over the years ask me how to make a Levain (Sourdough) Culture or if, rather, I could give them some of my own to use, which is usually an almost necessary action anyway during the typical care of a culture since it’s required to dispose of half before refreshing.
On the other hand though, I have found a system that works for my Levain and that makes no waste product in the end, saving me effort and money but still provides a good product.
To explain the waste, typically when you have a Levain, you feed after every use then store it and then get rid of that feeding and feed it again before using. This improves your yeasts environment (therefore the strength), keeps your yeast alive and happy, ensuring that your bread will rise with a good Levain Culture.
My no-waste method is simple and with the same end goal. I refresh (feed) my Levain the night before I intend to use it, let it rise / quadruple over-night or 8 hours, use about 80% of what’s there, and then store the extra 20% left over in the fridge until next time. Then I repeat by refreshing the leftover with a new feeding the night before I intend to use it again and so on.
Simple, and saves the money lost in the disposal of the extra flour used otherwise. Of course I typically make bread twice a week, but I’m sure that this can be stretched to a longer period of time like perhaps a whole week in between. After this you will most likely need to follow the typical feeding / usage requirements before making your dough.
There are other methods of storing your Levain using less water to make almost a hard dry dough you would just rehydrate before use, or using leftover dough instead, etc. but perhaps I’ll do another post in the future on different care methods for your culture, this post is simply on how to make one and a little bit about it.