A Special Guest:
We'll be joined by a Northwestern University yeast biologist, who will bring a number of yeasts in culture for us to sniff. Come and familiarize yourself with the single-celled organisms that give rise to our bread.
When it comes to sourdough, ask a hundred bakers about their respective methods, and you'll hear a hundred different answers. Some of the variables you may encounter are:
- Which flour(s) to "feed" the culture (bread flour, all-purpose flour, rye, or a combination of these);
- Hydration of the culture (from stiff to runny);
- How often to feed the culture (from twice/day to once/week);
- At what temperature to store the culture (from room temperature to the coldest part of the fridge);
- Whether or not to adjust the pH of the culture with an acid (such as apple cider vinegar).
A dominant influence in the health of a sourdough culture seems to be constancy: choose a method for maintaining the culture, and stick with it over the long haul. The yeast seem to like this approach, as it gives them a chance to get used to their environment and thrive. This is especially true when a culture is young; as the culture matures, it tends to be better able to recover from infrequent or irregular feedings.
The book my husband and I turn to again and again for help with sourdough (and many other aspects of bread making) is Jeffrey Hamelman's Bread. Hamelman's "Vermont Sourdough" is a classic, and a good place to start.
As always, baking to the focus topic is not a requirement for the event, simply a suggestion to inspire your baking. The only requirement is that you bring yeasted bread you have baked.