The sourdough starter is a natural leaven that can be made in many different ways... this recipe has been tested by Giallozafferano.
1. Put the bread flour in a bowl add the low-fat yogurt, mix the ingredients together after that turn it out onto a work surface and knead until it forms a soft, but not sticky dough.
2. Once the dough is ready, place in a bowl cut a cross into the top and cover with cling film; now poke 4-5 holes with a toothpick for air circulation, so that the yeasts can feed on sugars present in the dough, creating ethyl alcohol and carbon dioxide, to start the rising process. Keep the dough at a temperature between 78°F (26°C) and 82°F (28°C) for at least 48 hours.
3. The sourdough starter should appear collapsed, frothy and slightly increased in volume after 48 hours. Now we'll proceed with the first refreshment, take a small bowl and take 7 oz (200 g), of sourdough then add 7 oz (200 g) bread flour followed by 3.5 oz (100 g) of water, adjust the amount of water depending on how much your dough absorbs. Knead the mixture and form dough which is soft, and not sticky.
4. Store the rest of the sourdough starter , because the sourdough starter will be fed for the next 14 days and you don't want to end up with a huge mass of dough.
5. Once the dough is ready take a glass container, narrow and tall is better, so avoid large shallow containers, put in the dough, press it down, cover with cling film, make a few holes and leave it to rest for 24 hours at a temperature no higher than 78°F (26°C).
6. This was the first refreshment; you'll need to repeat this step, using the same ratio, for the next 14 days, so take a 7-oz (200 g) piece of dough, add 7 oz (200 g) of bread flour and 3,5 oz (100 g) of water. Follow the same steps for 14 days to make your sourdough starter stronger.
7. To know if the sourdough starter is ready to use or not follow these steps. After the 15th day, feed it once more, using the same ratio, and return the dough to the container, close the lid and let it sit for 4 hours: if it triples in volume, your sourdough starter is active and ready to use.
8. The sourdough starter is active; now store in the fridge in a narrow, tall glass container, covered with cling film or a lid, and feed it at least once a week, or it will die.
If you want to use it to make bread, for example, remember that the amount of the sourdough starter should be 30% of the weight of all the ingredients and, before refreshing, remember to remove the hardened crust on top if any, and use the moist centre.
If you want to make your sourdough starter even stronger, feed it once more before using, let it sit for 4 hours, then add to the rest of the ingredients.
The yogurt is called a starter, that is a sugar that feeds the yeasts present in the flour and in the air, causing them to produce carbon dioxide gas, which makes the dough rise. You can use a variety of starters, depending on the desired degree of sourness: you can use tomato or fruit, such as grapes, apples, etc, or also honey.