With yeasted bread you buy the yeast and add it to some warm liquid (perhaps milk & water) to wake it up and you mix in a bit of sugar so it has something to eat. The byproduct of the yeast eating the sugar is gaseous and that is what makes the bread rise and have little air holes. With a sourdough bread you ferment flour and the bacteria created during the fermentation process is like a natural yeast. Some might think of their starter as a flatulent teenager … you feed it sugar and flour and it grows and gets gassy :)
From a practical standpoint, the big difference between yeast and a sourdough starter is that it takes time for the flour to ferment and you have to tend to the mixture until it becomes active. To create the starter you mix flour and some filtered water in a jar, cover it with a porous material (I use cheesecloth at home but at work we use plastic wrap), then you put it in a place where the temperature is relatively stable and relatively warm (between 20 degC and 27 degC). You must use filtered water since chlorine in tap water kills the bacteria that makes the mixture active and creates the bubbles. The temperature of the ingredients is important … all of them should be in the low to mid twenties (between 20 degC and 27degC). The cover that you put over the jar needs to allow gas to escape so don’t wrap it too tightly if you are using plastic wrap.
Once the starter is created, it needs to be maintained until it becomes active. Every twelve hours or so you create a new starter and then take half of the previous starter and mix them together. Then cover it and leave it on the counter until the next “feeding”. The other half must be tossed in the organic waste bin :(
You need to keep feeding the starter until it starts to become active and bubbly. This could take anywhere from 3 days to ten days depending on the temperature on your counter. If it is relatively cool then it will take longer and if it is pretty warm then it will happen faster. It’s important that the temperature doesn’t fluctuate too rapidly during this initial growth period.
Once the starter is active and you can see bubbles through the side of your container (I use straight sided mason jars so I can see the activity), you can use it to make some bread (recipe coming soon).
30 g Sorghum flour
30 g Buckwheat flour
90 g Filtered water
Weight out the ingredients and mix them together in your container (mason jar, clear bowl, or a clear glass). Cover with cheese cloth or plastic wrap and place on your counter.