How are your starters? Mine is really getting active. Lots of bubbles, close together, and they come back quickly when I stir the mixture down. It also is starting to feel different when I stir. Before, it felt like stirring a cake batter, but now it feels frothy. Today, we'll add the usual ounce of flour and ounce of water and stir it occasionally.
When a starter is new, there are all sorts of yeasts and bacteria that come into it from the air, the flour, the baker's hands, and the water. In the beginning, they're all competing for survival, but the particular strains of yeast and bacteria that create a sourdough work together so well they're almost a sure bet to out-compete anything else in the mixture. Now that the bacteria and yeast are so active, there's not much chance that anything else will invade.
While not every sourdough culture will be wildly successful in terms of flavor, texture, rise, or any other criteria, the yeast and bacteria do a pretty good job of keeping out the types of things that could make you ill. Which is pretty amazing, if you think about it.
Go Back in Time...
Day Zero: What You'll Need »
Day 1: A Half-Ounce Flour and an Ounce of Water »
Day 2: No Feeding, Just Stirring »
Day 3: Feed Me More Flour! »
Day 4: 100% Hydration »
Day 5: Keep Feeding and Stirring! »
Day 6: Keep Stirring and Feeding! »
Day 7: Feed and Wait »