Every loaf of sourdough begins long before the dough comes together, before the flour and water meet, before the oven’s heat works its magic. It starts with something invisible, something alive—wild yeast and bacteria, tiny organisms that shape the flavor, texture, and rise of each loaf. As I work on my third loaf in this 1,000-loaf journey, I find myself reflecting on what’s really happening inside my jar of starter, a bubbling, unpredictable force that holds the key to great bread.
Sourdough is as much about patience as it is about science. And the science is truly fascinating.
A Healthy Starter: Where Yeast and Bacteria Thrive
A good starter is a living ecosystem, a home for wild yeast and lactic acid bacteria. Unlike commercial yeast, which has been bred for speed and reliability, wild yeast takes its time. It thrives in an acidic environment, feeds on complex carbohydrates, and produces the gases that create those airy, open crumbs we all love. The bacteria, meanwhile, break down sugars and create the tangy depth that gives sourdough its signature taste.
Feeding a starter is like feeding a pet—regular meals keep it strong. I feed mine a mix of 50% whole wheat flour and 50% bread flour, combined with equal parts water by weight. Whole wheat provides a rich source of wild yeast and nutrients, while the bread flour ensures strong gluten development when baking. Every feeding is a balancing act: too much food, and the yeast might not fully develop; too little, and it starves.
On this third loaf, I’ve noticed that my starter has become more predictable. It peaks at around six hours post-feeding, which tells me it’s ready to leaven dough. The smells change too—early on, it’s sweet like fresh flour, then it turns slightly tangy, and eventually, if left too long, it can take on a strong, almost vinegary note. Learning to read these cues is a skill that only comes with time, but it’s also what makes sourdough so rewarding.
The Science of Fermentation and Flavor Development
When I mix my dough, the starter gets to work. The yeast begins consuming the sugars in the flour, producing carbon dioxide, which forms the pockets of air that give sourdough its rise. Meanwhile, the bacteria create organic acids—lactic acid for a mild tang and acetic acid for a sharper bite. The balance between these acids depends on several factors: temperature, hydration, and feeding schedule.
For this loaf, I’m experimenting with a longer, cooler fermentation. Lower temperatures encourage more acetic acid, leading to a sharper tang, while warmer temperatures favor lactic acid, creating a gentler sourness. Since my last loaf had a fairly mild flavor, I’m curious to see if this adjustment will bring out more complexity. I’m also keeping an eye on hydration—too much water and my dough might spread too much in the oven; too little and it might lack that beautiful open crumb.
With each loaf, I’m fine-tuning these elements, adjusting fermentation time, starter strength, and dough hydration to see what works best. This is the beauty of sourdough—no two loaves are ever exactly the same, but each one teaches me something new.
Baking, Sharing, and the Gift of Bread
As my dough undergoes its final proof, I think about where this loaf will go. Every loaf I bake has a purpose beyond my own learning—I want each one to be shared. This time, I’ll be gifting it to a friend who has always been curious about sourdough but never had the time to bake. There’s something special about handing someone a freshly baked loaf, still warm, with that deep golden crust and unmistakable aroma. It’s not just food; it’s an invitation, a conversation, a reminder that the simplest things—flour, water, time—can create something meaningful.
When I pull the loaf from the oven, I already know I’ve learned something new. The crust has better blistering, the crumb looks more open, and the flavor—well, that will have to wait until the first slice. But I already know one thing: I’ll take what I’ve learned, make my notes, and get ready for loaf number four.
Because this journey isn’t just about baking bread. It’s about understanding it, sharing it, and continuing to learn with every single loaf.