(* Sourdough is a dough containing a lactobacillus culture, usually in symbiotic combination with yeasts. Sourdough bread is made by using a small amount (20-25 percent) of starter dough (sometimes known as "the mother sponge"), which contains the culture, and mixing it with new flour and water, check http://en.wikipedia.org/wiki/Sourdough )
The sourdough is the basic ingredient to make bread. You can think at it like a yeast that needs to be added to the mixture of flour and water that make the bread. No sourdough=no bread.
To be kept alive, the sourdough needs to be refreshed, with add of flour and water.
Always use glass or ceramic recipients to keep the sourdough, and wood spoon or hands to mix it: plastic IS NOT GOOD because the pastamadre has to breath and it would stop it to grow.
Let’s say you have 50grams of sourdough: the re-freshening has to be done from every 6 hours (minimum) until every 2 or 3 days maximum and has to be kept in the fridge during the summer.
The sourdough has to be refreshed adding flour in a relation of 1:4 (1 unit sourdough plus 4 units of flour and 4 units of water). So, to make an example, to refresh 50 grams of sourdough, add 200 gr. of flour and 200 gr. of water (you can use a glass to make the measurements).
If you want to have 2kg of bread, you will need 500-600 grams of sourdough. This means that you will need to refresh it several times to reach the right quantity. Bear in mind, you need to wait at least 6 hours between a refreshment and the other.
If you are not planning to make bread for some time and you want to keep the sourdough, put it in a glass recipient and cover it completely with olive oil. This process will conserve the sourdough for 10-15 days.
Do not use all the sourdough in once: keep some separate from the pasta mixture so that you can reuse it for the next time.
TO MAKE 1Kg of BREAD:
You need 300 gr of sourdough;
1000 gr of flour;
700 + or - cl of water;
