A firm sourdough starter goes by many names and you may see it referred to as pasta madre, lievito madre, stiff starter etc.
It differs from the more common liquid starter due to its hydration. A liquid starter has 100% flour to water hydration while a stiff starter is around 50%. In addition to the hydration the taste is different as well. The stiffer the dough is the less acidic it becomes. For this this reason, it is often used in sweets, the most famous are panettone and pandoro Italian Christmas cakes.
A method that came from Piedmont keeps the stiff starter submerged in water to avoid too much bacteria from souring the starter. The downside to this method is if the starter is left too long it can dissolve. I like to just keep mine covered in the fridge and feed it once a week.
This type of sourdough is one of the oldest ways to make bread, especially in Italy. If you ever had a great bread in Italy and couldn’t tell if it was a sourdough or not, chances are this is the type of levain that was used. It is this starter that can only be used in the D.O.P. protected Altamura bread. I find it takes a bit longer to ferment than a liquid starter but the flavor is worth it.
Why does the starter need a bath and how often should you bathe it?
The goal is to keep too much acetic acid from building up in the starter. To accomplish this, and especially if making from a liquid starter, the starter needs a bath before we start to use it. After the initial bath, it only needs it if you forget to feed it for some time or it is getting to sour.
How often do I need to feed my starter?
I recommend when not using it to feed the starter once a week. For a normal feeding I do 120g starter, 120g water and 60g of flour. If I want to make bread the next day I will feed it before going to bed by using 200g starter, 200g four and 100g water. Let it rest overnight then you are ready to use it the next morning.
Check out our Italian Sourdough with pasta madre here
Pasta Madre (From Sourdough Starter)
Simple step by step instructions on how to convert your liquid sourdough starter to a stiff starter (pasta madre).
Day 3 (Day before baking)
Day 1 - Create the stiff starter
Combine the liquid starter and flour. Knead and form it into a ball of dough. Add a little but of flour if too sticky, being careful not to add too much.
Cover and let sit at room temperature for 12 hours.
Taking from the middle of the stiff starter, cut into 4 equal parts and add to a bowl. Add the flour and water. With the back of a spoon press the mix together to form a dough. Transfer to the counter and knead until smooth.
Use a rolling pin to roll out the dough into a strip. Use a bench scraper to help unstick it from the counter and fold in half then half again. Rotate the dough and repeat rolling out out. Do this a couple times until the dough is smooth. The final strip should be around 23x3 inches (60x8 cm). Next roll the dough lengthwise. Cut an X into the top and cover.
Let rise until doubled (3-4 hours) then refrigerate.See gallery for more pictures on kneading and rolling it out. The dough will be sticky but resist adding more flour. Instead rely on the bench scraper to help unstick the dough from the counter. You have to go quick when rolling. If you let the rolling pin rest of the dough for a few seconds it will start to stick.
Day 3 - Bathe the dough
Remove the dough from the fridge and let sit 30-60 minutes.
Add 4 cups of warm water to a bowl and sprinkle in the sugar without mixing. We want the sugar to be on the bottom. Taking from the middle of the stiff starter, cut into 4 equal parts. Squeeze the dough to remove any excess air. Add to the water and let sit for 20 minutes.
Squeeze out the dough and then proceed to feeding it.Bathing the dough will draw out the bacteria to feed on the sugar. This will reduce the sourness or acidity of the starter.
Day 3 - Feed the starterRepeat steps from Day 2 with the increased amount of flour. Let rise until doubled (3-4 hours). The dough is now ready to be used in your recipe or placed in the refrigerator.See notes in the description on regular feeding and letting rise overnight.