Freshly baked sourdough bread by Eduardo Morrell of Morrell's Bread

One Saturday morning last summer, my husband and I stopped by the Berkeley Farmers' Market to buy some seasonal produce. After filling our bags with fresh vegetables, we decided to try a loaf of bread from Morrell’s Bread. I can't recall what type of bread we ended up choosing, but we both remember that it was the best loaf of bread we'd ever had. So as I began to research this story, I tracked down Eduardo to learn more about his wonderful bread – and eventually profiled him in Science on the SPOT: Secrets of Sourdough.

“It all really started when I received my master’s degree in filmmaking at the San Francisco Art Institute," says Eduardo. "And through the Art Institute, I knew plenty of artists and stuff that were doing residencies at the Headlands Center for the Arts. I would go up to visit them every now and then to check out their studios…I had worked in restaurants to make money even while I was at the school…And at one point, the Headlands ended up hiring a new chef, Jessica Prentice, a very good friend of mine who now [helps to run] Three Stone Hearth…And I went and volunteered one day at their open studios. And lo and behold, there’s the brick oven and there was a French baker there who was using the brick oven: Laurent, who was leasing the space and baking bread. Both [were] really kind of were my first two culinary inspirations.”

Eduardo observed Laurent as he worked and began to develop an understanding and appreciation for how to mix and ferment doughs. He then left California for a year to work as an assistant for former Duke University professor and author Reynolds Price and baked bread for Mr. Reynolds on a weekly basis.

“Reynolds was always happy to wake up and have the smell of fresh bread in the house…It was kind of fun, and that’s really where I started to develop this kind of the interest in the science of it more. I started a sourdough culture in North Carolina, I brought this one from California, and I would bake at different times and see if the one from California was changing…When you’re baking on small scale like that, that’s when I really started doing all my R&D, you know, for eventually what would become Morrell’s Bread.”

QUEST on KQED Public Media.

Upon Eduardo’s return, both Jessica and Laurent had departed to begin other ventures, so he made the suggestion to the Headlands Center For the Arts to lease the kitchen so he could bake his bread. Morrell’s Bread has grown steadily since then and has been in business for 10 years.

Using a wood-fired brick oven (constructed and designed by the renowned Alan Scott) takes an incredible amount of planning and effort in order to bake all of the bread for his weekly appearances at the Berkeley Farmers' Markets, but he loves both the romance and the sustainable aspect of using it. “I really like baking out in the Golden Gate National Recreation Area and burning wood there. It is actually a very sustainable form of heat. You have one wood-fired brick oven in a biome for trees, and all the trees pretty much act as one big carbon scrubber. So there’s very little pollution that happens when you have a single fire happening in this big, open area.” Eduardo also feels that, “both gas-fired ovens and wood-fired ovens produce excellent bread. I think it’s a question of what your personal preference is and how you want to be perceived as a baker and how you want to be a baker. And so I really like the whole preciousness aspect of it, and it reminded me a lot of my career as a filmmaker in that I really liked working with film. I didn't like working with video. I felt that film was precious…And I think it’s a similar process with baking bread.”

To learn more about Morrell's Bread, check out this slideshow of Eduardo Morrell's typical day at the Headlands Center of the Arts:

37.829785 -122.522535

 Secrets of Sourdough Educator Guide

Since the Gold Rush days when prospectors baked loaves in their encampments, sourdough bread has been a beloved favorite of the Bay Area. But what is true sourdough bread? It's more than just the tangy flavor. Science on the SPOT visits with Maria Marco of UC Davis and baker Eduardo Morrell to learn more about the secret science of sourdough.

But that's because only San Francisco is home to a certain bacterium that bears its name– Lactobacillus sanfranciscensis.

Of course bread uses another microbe– the yeast that turns sugar into the air bubbles that lighten the loaf. For sourdough, though, local bacteria then add their secret ingredient. They eat up the yeast's waste and turn it into acid, making the bread San Francisco sour.

The bacteria also make the dough inhospitable for other microbes, keeping all that doughy goodness for the yeast and itself. The yeast and bacteria make such great partners because the yeast can't eat the sugar maltose, which the bacteria absolutely need.

San Franciscans have been noshing on this local concoction since at least the Gold Rush. Boudin Bakery first baked buns in 1849. Some bakeries even claim to have a "starter"– the bit of dough that contains yeast and bacteria– that's over a century old. They pinch off a piece of starter for every new loaf, and care for the dough with regular feedings of flour and water.

If you've got a favorite brand, chances are it's because of the unique mix of yeast and bacteria from that bakery. Other towns' sourdough will taste a little bit different because their bacteria aren't the San Francisco kind.

Want to whip up a loaf unique to your backyard? The Exploratorium has a recipe to make your own starter that will pick up local yeast and bacteria. Or if you prefer that authentic San Francisco flavor, buy the original.

For more on Lactobacillus sanfranciscensis, check out the Berkeley Science Review.

Amber Dance is the Quest Intern and a science communication student at UC Santa Cruz.

37.412163 122.052612