Before yeast was commercially
available, people made sourdough bread by capturing wild yeasts from the
air in a process called fermentation. Fermentation is gaining a lot of
attention lately because of all the health benefits including making
food more easily digestible, the presence of good bacteria (think
yogurt), etc.
FUN FACT: Alaskan Prospectors used to carry sourdough starter with them because they didn’t know when they would be able to buy supplies.
Click here to read the article
