Sourdough started about 6,000 years ago when human found out how to boost the leavening and fermentation of grains to be brewed into drinks or baked into bread. A portion of the fermented grains were then saved by people in the past to begin the fermentation of the next batch of bread. Sourdough was then born from this recurring practice. The saved part is now referred to as a sourdough starter. The bread made from the mix is called sourdough bread.
What is Sourdough?
A sourdough starter is described as a natural leaven, or a mix of liquid and grains where wild yeasts and bacteria thrive to flavor and leaven the bread dough. The yeasts thrive naturally on the grain surface, in the air or soil and in fruits and vegetables. The bacteria are specific strains of the benign bacteria Lactobacillus.
Yeast and lactobacilli live peacefully in a symbiotic relationship. Both do not try to get food from each other. Yeast actually helps feed lactobacilli in certain cases. Lactobacilli, in turn, create an acidic area that is conducive for the yeast. The acids inside the culture will serve as an antibiotic wherein the lactobacilli can provide a protective environment for yeast. Lactobacilli help bread rise as well. Similar to yeast, the bacteria digest simple sugars located in flour to produce carbon dioxide and ethanol. The acetic and lactic acids created add flavor to the bread, having a wide array of flavors. In certain periods, the bread can have a sour tang because of sourdough.
The Recipe
The ingredients you will need are 2 cups of all-purpose flour, 1 packet or 2.25 teaspoons of active dry yeast, 2 teaspoons of granulated sugar and 2 cups of warm water (about 110 to 115 degrees F). You can also get good results by using whole wheat flour. Whole wheat start will not have a lot of rising action compared to something made with white flour. You have to plan longer rising periods. Adding whole wheat flour together with white flour can also be done to cut rising time.
More Tips
If you add some sugar, you will boost the yeast process. Yeast feeds on sugar to get extra energy. Yeast will rise by feeding on the sugars inside the flour and getting rid of carbon dioxide in the process. Do not put in too much sugar, however. If the water you use has chlorine, you can use bottled water, tap water or distilled water instead. Make sure you set this out for 1 days before you make the starter. Chlorine can cease the yeast development.
Mix the yeast, sugar and flour together in a sterile container. Ideally, you should only use ceramic or glass to contain 2 quarts. Stir in the water and continue mixing until you create a thick paste. Cover the container using a dish cloth and allow to sit at 70 to 80 degrees F. Temperatures higher than 100 degrees F usually kill the yeast. Observe how the yeast rises as you finish the process for optimum results.